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1.
Environ Pollut ; 256: 113385, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31662261

RESUMO

Triazole resistance in Aspergillus fumigatus is a major cause of clinical inefficacy in the treatment of invasive aspergillosis (IA). The hypothesis that triazole fungicides have driven the development of resistance in A. fumigatus has garnered substantial attention due to the similar structure and global detection of antifungal resistant A. fumigatus (ARAF) isolates in the soil. However, there is little evidence linking the application of triazole fungicides to the emergence of ARAF in the soil. This study was conducted to test if the resistance in A. fumigatus and its associated mutations in cyp51A could be induced by propiconazole in liquid medium and soil. The results indicate that propiconazole can induce resistance by alteration of G138S in cyp51A, and the overexpression of cyp51A, AfuMDR3 and AfuMDR4. G138S in cyp51A was first detected in the soil and associated with resistance. The emergence of the ARAFs in the soil may depends upon the level of propiconazole, and the number of ARAFs in soil treated with propiconazole at 2- and 5-fold dose was much greater than those in soil treated at the recommended dosage. The current data indicate that propiconazole can induce triazole resistance in A. fumigatus and should be applied for agricultural purposes at levels at or below the recommended dosage to avoid the emergence of ARAF in the soil.


Assuntos
Antifúngicos/toxicidade , Aspergillus fumigatus/efeitos dos fármacos , Sistema Enzimático do Citocromo P-450/genética , Farmacorresistência Fúngica/efeitos dos fármacos , Proteínas Fúngicas/genética , Triazóis/toxicidade , Aspergillus fumigatus/genética , Farmacorresistência Fúngica/genética , Humanos , Testes de Sensibilidade Microbiana , Mutação , Solo/química , Microbiologia do Solo , Soluções
2.
Ecotoxicol Environ Saf ; 187: 109868, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31689623

RESUMO

The occurrence of azole antifungals in the environment presents one of the emerging concerns due to their ecotoxicological threat as well as their potential contribution to the evolution of drug resistant fungi in the environment. In this study, the occurrence of eight commonly prescribed azole antifungal drugs was seasonally determined in influent and effluent water samples from three wastewater treatment plants and a drinking water treatment plant in South Africa. In addition, the risk quotient (RQ) method was employed to investigate the potential ecological and human health risks associated with their presence in the wastewater and/or drinking water. Clotrimazole, econazole, fluconazole, itraconazole, ketoconazole and miconazole were detected at least once in the water samples, while posaconazole and voriconazole were not detected in any of the samples for all seasons at which the samples were collected. Fluconazole was detected at higher frequency (about 96%) with a concentration up to 9959.0 ng L-1. Clotrimazole had the second highest frequency of detection (about 33%) with a concentration up to 143.3 ng L-1. Statistically significant temporal variation in clotrimazole (p < 0.05) and spatial variation in fluconazole (p < 0.05) were observed. In general, the preliminary ecological risk assessment based on risk quotient (RQ) calculation indicated that there is currently no high risk against aquatic organisms (Algae, Daphnia and Fish) related to the azole antifungals. Meanwhile, human health risk assessment demonstrated that fluconazole represented high risk in drinking water. Furthermore, risk estimates showed a potential for the detected concentrations of fluconazole and itraconazole in water samples to pose moderate to high risk for development of antifungal drug resistance. Some of the azole antifungal drugs are ubiquitous in the wastewater and future monitoring and validation studies should be conducted for those drugs that seem to pose human health and ecological risks.


Assuntos
Antifúngicos/análise , Azóis/análise , Água Potável/química , Monitoramento Ambiental/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Antifúngicos/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Azóis/toxicidade , Farmacorresistência Fúngica , Ecotoxicologia , Humanos , Medição de Risco , África do Sul , Poluentes Químicos da Água/toxicidade
3.
Future Microbiol ; 14: 1087-1097, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31512522

RESUMO

Aim: In this work, mastoparan analog peptides from wasp venom were tested against Candida albicans and safety assays were performed using cell culture and model zebrafish. Materials & methods: Minimal inhibitory concentration was determined and toxicity was performed using human skin keratinocyte and embryo zebrafish. Also, permeation of peptides through embryo chorion was performed. Results: The peptides demonstrated anti-C. albicans activity, with low cytotoxicity and nonteratogenicity in Danio rerio. The compounds had different permeation through chorion, suggesting that this occurs due to modifications in their amino acid sequence. Conclusion: The results showed that the studied peptides can be used as structural study models for novel potential antifungal agents.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Peptídeos/farmacologia , Venenos de Vespas/farmacologia , Animais , Antifúngicos/administração & dosagem , Antifúngicos/efeitos adversos , Antifúngicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Peptídeos e Proteínas de Sinalização Intercelular/efeitos adversos , Peptídeos e Proteínas de Sinalização Intercelular/toxicidade , Queratinócitos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Peptídeos/administração & dosagem , Peptídeos/efeitos adversos , Peptídeos/toxicidade , Venenos de Vespas/administração & dosagem , Venenos de Vespas/efeitos adversos , Venenos de Vespas/toxicidade , Peixe-Zebra
4.
Curr Drug Deliv ; 16(7): 645-653, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31362675

RESUMO

BACKGROUND: Amphotericin B (AmB) is important for the treatment of systemic fungal infections. Nowadays, only intravenous administration (IV) of AmB has been available due to its low aqueous solubility. Two forms of AmB are available. The first is Fungizone®, a mixture of AmB and sodium deoxcycholate that produces severe nephrotoxicity. The second are lipid-based formulations that reduce nephrotoxicity, but they are costly and require higher dose than Fungizone®. Thus, a cheaper delivery system with reduced AmB toxicity is required. OBJECTIVE: To develop and characterize AmB loaded-nanostructured lipid carriers (AmB-loaded NLCs) for IV administration to reduce AmB toxicity. METHODS: AmB-loaded NLCs with different solid lipids were prepared by the high-pressure homogenization technique. Their physicochemical properties and the drug release profile were examined. The molecular structure of AmB, antifungal and hemolysis activities of developed AmB-loaded NLCs were also evaluated. RESULTS: AmB-loaded NLCs ~110 to ~140 nm in diameter were successfully produced with a zeta potential of ~-19 mV and entrapment efficiency of ~75%. In vitro release showed fast release characteristics. AmB-loaded NLCs could reduce the AmB molecular aggregation as evident from the absorbance ratio of the first to the fourth peak showing a partial aggregation of AmB. This result suggested that AmB-loaded NLCs could offer less nephrotoxicity compared to Fungizone®. In vitro antifungal activity of AmB-loaded NLCs showed a minimum inhibitory concentration of 0.25 µgmL-1. CONCLUSION: AmB-loaded NLCs present high potential carriers for effective IV treatment with prolonged circulation time and reduced toxicity.


Assuntos
Anfotericina B , Antifúngicos , Portadores de Fármacos , Nanoestruturas , Administração Intravenosa , Anfotericina B/administração & dosagem , Anfotericina B/química , Anfotericina B/toxicidade , Animais , Antifúngicos/administração & dosagem , Antifúngicos/química , Antifúngicos/toxicidade , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Lipídeos/administração & dosagem , Lipídeos/química , Lipídeos/toxicidade , Nanoestruturas/administração & dosagem , Nanoestruturas/química , Nanoestruturas/toxicidade , Ovinos
5.
Arch Pharm (Weinheim) ; 352(10): e1900092, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463959

RESUMO

Due to their high specificity and efficacy, triazoles have become versatile antifungals to treat fungal infections in human healthcare and to control phytopathogenic fungi in agriculture. However, azole resistance is an emerging problem affecting human health as well as food security. Here we describe the synthesis of 10 novel {2-(3-R-1H-1,2,4-triazol-5-yl)phenyl}amines. Their structure was ascertained by liquid chromatography-mass spectrometry, 1 H and 13 C NMR, and elemental analysis data. Applying an in vitro growth assay, these triazoles show moderate to significant antifungal activity against the opportunistic pathogen Aspergillus niger, 12 fungi (Fusarium oxysporum, Fusarium fujikuroi, Colletotrichum higginsianum, Gaeumannomyces graminis, Colletotrichum coccodes, Claviceps purpurea, Alternaria alternata, Mucor indicus, Fusarium graminearum, Verticillium lecanii, Botrytis cinerea, Penicillium digitatum) and three oomycetes (Phytophtora infestans GL-1, P. infestans 4/91; R+ and 4/91; R-) in the concentration range from 1 to 50 µg/ml (0.003-2.1 µM). Frontier molecular orbital energies were determined to predict their genotoxic potential. Molecular docking calculations taking into account six common fungal enzymes point to 14α-demethylase (CYP51) and N-myristoyltransferase as the most probable fungal targets. With respect to effectiveness, structure-activity calculations revealed the strong enhancing impact of adamantyl residues. The shown nonmutagenicity in the Salmonella reverse-mutagenicity assay and no violations of drug-likeness parameters suggest the good bioavailability and attractive ecotoxicological profile of the studied triazoles.


Assuntos
Antifúngicos/síntese química , Desenho de Fármacos , Fungos Mitospóricos/efeitos dos fármacos , Triazóis/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/crescimento & desenvolvimento , Simulação de Acoplamento Molecular , Estrutura Molecular , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Relação Estrutura-Atividade , Triazóis/química , Triazóis/farmacologia , Triazóis/toxicidade
6.
Biomed Res Int ; 2019: 1851740, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275963

RESUMO

The human opportunistic fungal pathogen Candida albicans causes a severe health burden while the biofilms formed by C. albicans present a kind of infections that are hard to cure, highlighting the pressing need for new antifungal drugs against C. albicans. This study was to explore the antifungal activities of lycorine hydrochloride (LH) against C. albicans. The minimal inhibitory concentration (MIC) of LH against C. albicans SC5314 was 64 µM. Below its MIC, LH demonstrated antivirulence property by suppressing adhesion, filamentation, biofilm formation, and development, as well as the production of extracellular phospholipase and exopolymeric substances (EPS). The cytotoxicity of LH against mammalian cells was low, with half maximal inhibitory concentrations (IC50) above 256 µM. Moreover, LH showed a synergistic effect with AmB, although its interaction with fluconazole, as well as caspofungin, was indifferent. Thus, our study reports the potential use of LH, alone or in combination with current antifungal drugs, to fight C. albicans infections.


Assuntos
Alcaloides de Amaryllidaceae/farmacologia , Candida albicans/patogenicidade , Fenantridinas/farmacologia , Adesividade/efeitos dos fármacos , Alcaloides de Amaryllidaceae/química , Alcaloides de Amaryllidaceae/toxicidade , Antifúngicos/química , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Morte Celular/efeitos dos fármacos , AMP Cíclico/metabolismo , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Hifas/efeitos dos fármacos , Fenantridinas/química , Fenantridinas/toxicidade , Fosfolipases/metabolismo , Virulência/efeitos dos fármacos
7.
Environ Toxicol Pharmacol ; 71: 103210, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31280003

RESUMO

Among the vast list of xenobiotics that may promote harmful effects in aquatic ecosystems, pharmaceuticals are currently a prominent class due to their ability to persist in these environments and also due to the lack of information regarding their effects on the different components of the aquatic biota. Antifungals in particular, despite their massive use, are not extensively studied in environbmental terms. The main objective of this study was to characterize the toxicity of the antifungal clotrimazole to the aquatic organism Daphnia magna. To attain this purpose, the effects of this compound were measured, focusing on the determination of acute lethality, and quantification of biomarkers, such as neurotoxicity (soluble cholinesterases, ChEs); and oxidative stress and metabolism (such as catalase, CAT; and glutathione-S-transferases, GSTs). The toxicity assessment with biomarkers was based on animals exposed to concentrations similar to those already found in surface waters in order to increase the ecological relevance of the obtained data. The results showed that exposure to clotrimazole was able to induce significant increases in both CAT amd GSTs activities. ChE activity was not significantly altered after clotrimazol exposure. In view of the above, it is concluded that the drug studied caused adverse effects in terms of oxidative stress, at an ecological relevant levels, showing that the presence of clotrimazol in the wild is not innocuous.


Assuntos
Antifúngicos/toxicidade , Clotrimazol/toxicidade , Daphnia/efeitos dos fármacos , Biomarcadores Ambientais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Daphnia/metabolismo , Relação Dose-Resposta a Droga , Dose Letal Mediana , Testes de Toxicidade Aguda
8.
Phytomedicine ; 63: 153033, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31352284

RESUMO

BACKGROUND: The emergence of antibiotic resistant microorganisms presents a worldwide problem that requires novel antibiotic and non-antibiotic strategies, and biofilm formation is a mechanism of drug resistance utilized by diverse microorganisms. The majority of microorganisms live in biofilms that help their survival against starvation, antimicrobial agents, and immunological defense systems. Therefore, it is important novel compounds be identified that inhibit biofilm formation and cell survival without drug resistance. STUDY DESIGN: In this study, the antimicrobial and antibiofilm activities of five prenylated flavanones (Okinawan propolins) isolated from fruits of Macaranga tanarius (L.) were investigated against 14 microorganisms including 10 pathogens. RESULTS: Of these five propolins, propolin D at 5-10 µg/ml significantly inhibited biofilm formation by three Staphylococcus aureus strains, a Staphylococcus epidermidis strain, and a Candida albicans with MICs from 10 to 50 µg/ml, and in C. albicans, propolin D was found to inhibit biofilm formation by reducing cell aggregation and downregulated the expressions of hypha/biofilm-related genes including ECE1 and HWP1. Interestingly, at sub-MIC concentrations (10-50 µg/ml), propolin D significantly inhibited biofilm formation by enterohemorrhagic E. coli O157:H7, uropathogenic E. coli O6:H1, and Acinetobacter baumannii without affecting planktonic cell growth, but did not inhibit biofilm formation by a commensal E. coli K-12 strain, three probiotic Lactobacillus plantarum strains, or two Pseudomonas aeruginosa strains. And, propolin D reduced fimbriae production by E. coli O157:H7 and repressed gene expression of curli fimbriae genes (csgA and csgB). Also, propolin D was minimally toxic in a Caenorhabditis elegans nematode model. CONCLUSION: These findings show that prenylated flavanones, especially propolin D from Macaranga tanarius (Okinawan propolis), should be considered potential candidates for the development of non-toxic antibacterial and antifungal agents against persistent microorganisms.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Euphorbiaceae/química , Flavanonas/farmacologia , Flavonoides/farmacologia , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Antifúngicos/química , Antifúngicos/toxicidade , Biofilmes/efeitos dos fármacos , Caenorhabditis elegans/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Avaliação Pré-Clínica de Medicamentos , Escherichia coli O157/efeitos dos fármacos , Flavanonas/química , Flavanonas/toxicidade , Flavonoides/química , Flavonoides/toxicidade , Testes de Sensibilidade Microbiana , Prenilação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Testes de Toxicidade
10.
J Med Microbiol ; 68(7): 1047-1052, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31169488

RESUMO

INTRODUCTION: Miramistin is a topical antiseptic with broad antimicrobial activity that was developed in the Soviet Union during the Cold War. AIM: To investigate the antifungal activity of miramistin against clinically relevant drug-resistant fungi. METHODOLOGY: The in vitro activity of miramistin was determined following Clinical and Laboratory Standards Institute (CLSI) guidelines. Mammalian cell toxicity was tested using a McCoy cell line and topical and systemic tolerability, and in vivo efficacy was tested using Galleria mellonella models. RESULTS: The minimal inhibitory concentration (MIC) range against fungi was 1.56-25 mg l-1 (GM 3.13 mg l-1 ). In the G. mellonella model, miramistin provided potent survival benefits for Candida albicans and Aspergillus fumigatus infection. Miramistin was tolerated by McCoy cell lines at concentrations up to 1000 mg l-1 and was systemically safe in G. mellonella at 2000 mg kg-1. Topical administration at 32 000 mg l-1 was well tolerated with no adverse effects. CONCLUSION: These findings support further investigation of miramistin and suggest its possible use for treatment of superficial fungal infections.


Assuntos
Antifúngicos/farmacologia , Compostos de Benzalcônio/farmacologia , Fungos/efeitos dos fármacos , Animais , Antifúngicos/administração & dosagem , Antifúngicos/toxicidade , Compostos de Benzalcônio/administração & dosagem , Compostos de Benzalcônio/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Farmacorresistência Fúngica , Camundongos , Testes de Sensibilidade Microbiana , /efeitos dos fármacos
11.
Int J Biol Macromol ; 135: 808-814, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31158421

RESUMO

In synthesis of silver nanoparticles (AgNPs), the composition of the stabilizer used can be closely related to the effectiveness of the synthesis and to the shape of the final nanoparticles. Recently, the use of collagen as an effective nanoparticle stabilization agent was reported. In this work, synthesis of silver nanoparticles using mixed capping agents is reported. The capping agents used were cashew gum-hydrolyzed collagen; kappa carrageenan-hydrolyzed collagen, and agar-hydrolyzed collagen. We evaluated antibacterial action against Gram-positive and Gram-negative bacteria, as well as antifungal activity and cytotoxicity. Homogenized mixtures of collagen and aqueous cashew gum, carrageenan or agar respectively were used to produce the nanoparticles AgNPcolCashew, AgNPcolCarr and AgNPcolAgar. AgNP characterization was performed using Uv-vis, XRD, TEM and DLS and the biological activities were assayed using MIC and MBC analyses for both antibacterial and antifungal application. Results showed that the AgNPcollcar sample showed the strongest bacterial inhibition with MIC values of 62.5 and 31.25 µM/mL Ag against E. coli and P. aeruginosa respectively. Interestingly, AgNPcollAgar also presented the lowest cytotoxicity when compared with other AgNPs and AgNO3.


Assuntos
Colágeno/química , Nanopartículas Metálicas/química , Polímeros/química , Prata/química , Prata/farmacologia , Animais , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Candida albicans/efeitos dos fármacos , Técnicas de Química Sintética , Escherichia coli/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Hidrólise , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Nanotecnologia , Pseudomonas aeruginosa/efeitos dos fármacos , Ovinos , Prata/toxicidade
12.
Eur J Med Chem ; 177: 374-385, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31158751

RESUMO

To discover broad spectrum antifungal agents, two strategies were applied, and a novel class of l-amino alcohol derivatives were designed and synthesized. 3-F substituted compounds 14i, 14n, 14s and 14v exhibited excellent antifungal activities with broad antifungal spectra against C. albicans and C. tropicalis, with MIC values in the range of 0.03-0.06 µg/mL, and against A. fumigatus and C. neoformans, with MIC values in the range of 1-2 µg/mL. Notably, Compounds 14i, 14n, 14s and 14v also displayed moderate activities against fluconazole-resistance strains 17# and CaR that were isolated from AIDS patients. Moreover, only compounds in the S-configuration showed antifungal activity. Preliminary mechanistic studies showed that the potent antifungal activity of compound 14v stemmed from inhibition of C. albicans CYP51. Compounds 14n and 14v were almost nontoxic to mammalian A549 cells, and their stability in human plasma was excellent.


Assuntos
Amino Álcoois/farmacologia , Antifúngicos/farmacologia , Células A549 , Amino Álcoois/síntese química , Amino Álcoois/metabolismo , Amino Álcoois/toxicidade , Antifúngicos/síntese química , Antifúngicos/metabolismo , Antifúngicos/toxicidade , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/enzimologia , Candida albicans/efeitos dos fármacos , Candida tropicalis/efeitos dos fármacos , Domínio Catalítico , Cryptococcus neoformans/efeitos dos fármacos , Desenho de Fármacos , Estabilidade de Medicamentos , Ergosterol/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Ligação Proteica , Estereoisomerismo , Esterol 14-Desmetilase/química , Esterol 14-Desmetilase/metabolismo , Relação Estrutura-Atividade
13.
PLoS One ; 14(6): e0218569, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31220147

RESUMO

Failures in control of tan spot of pyrethrum, caused by Didymella tanaceti, has been associated with decreased sensitivity within the pathogen population to the succinate dehydrogenase inhibitor (SDHI) fungicide boscalid. Sequencing the SdhB, SdhC, and SdhD subunits of isolates with resistant and sensitive phenotypes identified 15 mutations, resulting in three amino acid substitutions in the SdhB (H277Y/R, I279V), six in the SdhC (S73P, G79R, H134R, H134Q, S135R and combined H134Q/S135R), and two in the SdhD (D112E, H122R). In vitro testing of their boscalid response and estimation of resistance factors (RF) identified isolates with wild-type (WT) Sdh genotypes were sensitive to boscalid. Isolates with SdhB-I279V, SdhC-H134Q and SdhD-D112E exhibited moderate resistance phenotypes (10 ≥ RF < 100) and isolates with SdhC-H134R exhibited very high resistance phenotypes (RF ≥ 1000). All other substitutions were associated with high resistance phenotypes (100 ≥ RF < 1000). High-resolution melt assays were designed and used to estimate the frequencies of substitutions in four field populations (n = 774) collected in August (pre-boscalid application) and November (post-boscalid application) 2012. The SdhB-H277Y, SdhC-H134R and SdhB-H277R genotypes were most frequently observed across populations at 56.7, 19.0, and 10.3%, respectively. In August 92.9% of D. tanaceti contained a substitution associated with decreased sensitivity. Following boscalid application, this increased to 98.9%, with no WT isolates detected in three fields. Overlaying previously obtained microsatellite and mating-type data revealed that all ten recurrent substitutions were associated with multiple genotypes. Thus, boscalid insensitivity in D. tanaceti appears widespread and not associated with clonal spread of a limited pool of individuals.


Assuntos
Antifúngicos/toxicidade , Ascomicetos/genética , Compostos de Bifenilo/toxicidade , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Niacinamida/análogos & derivados , Succinato Desidrogenase/genética , Ascomicetos/efeitos dos fármacos , Ascomicetos/patogenicidade , Mutação de Sentido Incorreto , Niacinamida/toxicidade , Tanacetum/microbiologia
14.
Toxicol Mech Methods ; 29(7): 531-541, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31099283

RESUMO

Ketoconazole (KTZ) and itraconazole (ITZ) are antifungal agents that have a broad spectrum of activity against fungal pathogens. However, the therapeutic indications of many antifungal drugs, including those of the azole group, are restricted due to possible hepatotoxicity. We performed toxicogenomic analyses using in vivo and in vitro models to investigate the molecular mechanisms underlying the hepatotoxicity of two azole antifungal drugs. C57BL/6 male mice were treated daily with KTZ or ITZ, sacrificed at days 1 or 7, and the serum biochemistry and histopathology results showed that the KTZ-treated mice exhibited hepatotoxicity. Primary hepatocytes from C57BL/6 mice also exposed to KTZ or ITZ, and the cytotoxic effects of KTZ and ITZ were evaluated; KTZ exerted a greater cytotoxic effect than ITZ. The gene expression profiles in the livers of the 7-day-treated group and primary hepatocytes of the 24-h-treated group for both KTZ and ITZ were comparatively analyzed. Differentially expressed genes were selected based on the fold-changes and statistical significance, and the biological functions were analyzed using ingenuity pathways analysis. The results revealed that genes related to cholesterol synthesis were overexpressed in the liver in the KTZ-treated group, whereas expression of those related to acute phase injury was significantly altered in the ITZ-treated group. Causal gene analyses suggested that sterol regulatory element-binding transcription factors are key regulators that activate the transcription of target genes associated with the hepatotoxicity induced by oral KTZ. These findings enhance our understanding of the molecular mechanisms underlying the hepatotoxicity of azole drugs.


Assuntos
Antifúngicos/toxicidade , Azóis/toxicidade , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Hepatócitos/metabolismo , Hepatócitos/patologia , Itraconazol/toxicidade , Cetoconazol/toxicidade , Fígado/metabolismo , Fígado/patologia , Masculino , Metabolômica , Camundongos Endogâmicos C57BL , Cultura Primária de Células
15.
J Chemother ; 31(5): 267-273, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31140369

RESUMO

The aim of this study was to evaluate the effects of topical voriconazole with histopathological and immunohistochemical analysis of the conjunctiva in rats. Twenty-eight Sprague Dawley rats were divided into four groups as two study (S1, S2) and two control (C1, C2). Voriconazole was instilled four times daily to S1, S2 rats. Physiologic saline (0.9%) was instilled four times daily in C1 and C2 rats. S1 and C1 were followed in a dark room; S2 and C2 were held in a room with sunlight. Impression cytology was performed at 0, 15, 30, 45 and 60th d after instillations. After 2 months of treatment conjunctival tissue was removed for histological and immunohistochemical analysis. In impression cytology evaluation, there was no difference between S1 and S2. At 60 d the difference between S1 and C1 was significant. In other comparisons, there was no difference between S1 and C1, C2. The scores of S2 was higher than C1 and C2 for all comparisons except 15th day scores of S2 and C2. In study groups, epithelial and gland degeneration were higher in S2, but inflammation scores were similar. The comparison of immunreactivity of ERK, TGFß and E-cadherin were different in the study groups than the control groups for all comparisons. In conclusion, voriconazole has side effects due to phototoxicity including squamous cell carcinoma. Clinicians should particularly be careful with the long-term use of topical voriconazole and should follow-up patients strictly in terms of ocular surface alterations.


Assuntos
Antifúngicos/administração & dosagem , Túnica Conjuntiva/patologia , Imuno-Histoquímica/métodos , Inflamação/patologia , Voriconazol/administração & dosagem , Administração Tópica , Animais , Antifúngicos/toxicidade , Túnica Conjuntiva/efeitos dos fármacos , Inflamação/induzido quimicamente , Masculino , Ratos , Ratos Sprague-Dawley , Voriconazol/toxicidade
16.
Int J Pharm ; 565: 447-457, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31071418

RESUMO

Identifying the critical process parameters (CPPs) of a complex drug product manufacture and the associated impact on critical quality attributes (CQAs) is essential to the development and quality control of both new and generic drugs. AmBisome, a liposomal amphotericin B (AMB) macrolide antibiotic widely adopted as an important antifungal drug product, was used as a model complex drug product in the current study. This study investigated how multi-step production approaches and related manufacturing conditions may affect essential physico-chemical and toxicological properties of the final drug product. A key challenge in the manufacture and analysis of liposomal AMB was the drug substance's propensity to aggregate, with associated poor solubility in water and organic solvents. This study identified three key CPPs in a four step manufacturing process: (i) proper acidification during formation of the drug-lipid complexes (Step 1), (ii) liposome heat curing following liposomal particle sizing (Step 3), and (iii) flash-freezing at the initial stages of the lyophilization cycle (Step 4). Over-acidification led to rapid degradation of the drug, whereas under-acidification hampered full solubilization and formation of the soluble drug-lipid complexes. Extended heat treatment of the formed liposomes at 65 °C, just above the lipid phase transition temperature, brought dramatic changes in the aggregated state and/or packing of the drug in the liposomal bilayer, as followed by the complex changes in the UV/Vis spectra. Such thermal conditioning resulted in a five- to ten-fold reduction in the in-vitro toxicity of the drug product, bringing it close to the values for AmBisome used as control and measured by the RBC assay. Finally, flash-freezing conditions during lyophilization was critical to prevent aggregation and maintaining the 80-120 nm liposome size when reconstituted. Our research found that changes in the amphotericin's UV/Vis spectra were a sensitive CQA measure and provided a set of quantitative parameters for a facile non-destructive process monitoring in-situ, as well as for comparison of the quality of final formulations.


Assuntos
Anfotericina B/química , Antibacterianos/química , Antifúngicos/química , Anfotericina B/toxicidade , Animais , Antibacterianos/toxicidade , Antifúngicos/toxicidade , Composição de Medicamentos , Eritrócitos/efeitos dos fármacos , Congelamento , Temperatura Alta , Tamanho da Partícula , Ratos
17.
Carbohydr Polym ; 217: 207-216, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31079678

RESUMO

The design of functional materials capable of fighting fungal infections is of paramount importance given the intricate problem of multidrug-resistant pathogenic fungi. Herein, nanocomposites consisting of cross-linked poly([2-(methacryloyloxy)ethyl]trimethylammonium chloride) (PMETAC) and bacterial nanocellulose (BNC) were prepared, characterized and tested towards the polymorphic fungus Candida albicans. The BNC three-dimensional network enabled the in-situ polymerization of the non-toxic and bioactive quaternary-ammonium monomer, which originated transparent nanocomposites containing 10 and 40 wt.% of cross-linked PMETAC. Furthermore, the nanocomposites exhibit UV-A and UV-B blocking properties, high water-uptake capacity, thermal stability up to 200 °C, good viscoelastic (storage modulus > 1.7 GPa) and mechanical (Young's modulus ≥2.4 GPa) properties and are non-cytotoxic to human keratinocytes (HaCaT cells). The fungal inactivation reached a 4.4 ± 0.14-log CFU reduction for the nanocomposite containing only 10 wt.% of cross-linked PMETAC. Hence, these bioactive and non-cytotoxic materials can constitute potentially effective systems for the treatment of C. albicans infections.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Celulose/química , Metacrilatos/farmacologia , Nanocompostos/química , Antifúngicos/química , Antifúngicos/toxicidade , Linhagem Celular , Celulose/toxicidade , Humanos , Metacrilatos/química , Metacrilatos/toxicidade , Testes de Sensibilidade Microbiana , Nanocompostos/toxicidade , Temperatura , Resistência à Tração , Água/química
18.
Biofouling ; 35(2): 129-142, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30950296

RESUMO

The present study investigated the antimicrobial, anti-adhesion and anti-biofilm activity of the modified synthetic molecules nitrochalcone (NC-E05) and pentyl caffeate (C5) against microorganisms which have a high incidence in hospital-acquired infections. The compounds were further tested for their preliminary systemic toxicity in vivo. NC-E05 and C5 showed antimicrobial activity, with minimum inhibitory concentrations (MICs) ranging between 15.62 and 31.25 µg ml-1. Treatment with NC-E05 and C5 at 1 × MIC and/or 10 × MIC significantly reduced mono or mixed-species biofilm formation and viability. At MIC/2, the compounds decreased microbial adhesion to HaCaT keratinocytes from 1 to 3 h (p < 0.0001). In addition, NC-E05 and C5 demonstrated low toxicity in vivo in the Galleria mellonella model at anti-biofilm concentrations. Thus, the chemical modification of these molecules proved to be effective in the proposed anti-biofilm activity, opening opportunities for the development of new antimicrobials.


Assuntos
Anti-Infecciosos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Ácidos Cafeicos/farmacologia , Chalconas/farmacologia , Animais , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Anti-Infecciosos/toxicidade , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Biofilmes/crescimento & desenvolvimento , Ácidos Cafeicos/toxicidade , Candida albicans/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Chalconas/toxicidade , Infecção Hospitalar/prevenção & controle , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mariposas/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
19.
Regul Toxicol Pharmacol ; 106: 152-168, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31026541

RESUMO

Mefentrifluconazole (trade name: Revysol®) is an agrochemical active ingredient from the new sub-class of isopropanol-triazole fungicides, with high selective fungicide activity. A full program of toxicity testing conducted according to OECD guidelines has shown mefentrifluconazole (MFZ) to be non-genotoxic and non-carcinogenic. Repeated dose studies in rats, mice and dogs identified the liver as the main target organ. Prenatal developmental toxicity studies in rats and rabbits did not indicate treatment-related embryofetal toxicity or teratogenicity up to the highest dose levels tested. In a two-generation dietary study in rats, the high dose level resulted in reduced food consumption and body weight gain throughout the dosing-period. Mating performance and fertility, estrous cycles, gestation length and pre-and post-natal survival of offspring were essentially unaffected and there was no evidence of masculinization of female pups or feminization of male pups. The screening strategy that led to the selection of MFZ was aimed to identify candidates with both high fungicidal activity and minimal likelihood of adverse side effects thought to arise from aromatase inhibition. The success of the selection strategy has been illustrated for MFZ by the absence in toxicity studies of effects that would indicate an endocrine disrupting potential.


Assuntos
Antifúngicos/efeitos adversos , Antifúngicos/toxicidade , Fluconazol/análogos & derivados , Animais , Peso Corporal/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Feminino , Fluconazol/efeitos adversos , Fluconazol/toxicidade , Humanos , Fígado/efeitos dos fármacos , Masculino , Camundongos , Coelhos , Ratos
20.
Biosensors (Basel) ; 9(1)2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30897802

RESUMO

Dioclea reflexa bioactive compounds have been shown to contain antioxidant properties. The extracts from the same plant are used in traditional medical practices to treat various diseases with impressive outcomes. In this study, ionic mobility in Saccharomyces cerevisiae cells in the presence of D. reflexa seed extracts was monitored using electrochemical detection methods to link cell death to ionic imbalance. Cells treated with ethanol, methanol, and water extracts were studied using cyclic voltammetry and cell counting to correlate electrochemical behavior and cell viability, respectively. The results were compared with cells treated with pore-forming Amphotericin b (Amp b), as well as Fluconazole (Flu) and the antimicrobial drug Rifampicin (Rif). The D. reflexa seed water extract (SWE) revealed higher anodic peak current with 58% cell death. Seed methanol extract (SME) and seed ethanol extract (SEE) recorded 31% and 22% cell death, respectively. Among the three control drugs, Flu revealed the highest cell death of about 64%, whereas Amp b and Rif exhibited cell deaths of 35% and 16%, respectively, after 8 h of cell growth. It was observed that similar to SWE, there was an increase in the anodic peak current in the presence of different concentrations of Amp b, which also correlated with enhanced cell death. It was concluded from this observation that Amp b and SWE might follow similar mechanisms to inhibit cell growth. Thus, the individual bioactive compounds from the water extracts of D. reflexa seeds could further be purified and tested to validate their potential therapeutic application. The strategy to link electrochemical behavior to biochemical responses could be a simple, fast, and robust screening technique for new drug targets and to understand the mechanism of action of such drugs against disease models.


Assuntos
Antifúngicos/toxicidade , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Extratos Vegetais/toxicidade , Saccharomyces cerevisiae/efeitos dos fármacos , Sobrevivência Celular , Dioclea/química , Sementes/química , Testes de Toxicidade/métodos
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