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1.
Mol Cell ; 73(4): 749-762.e5, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30661981

RESUMO

The introduction of azole heterocycles into a peptide backbone is the principal step in the biosynthesis of numerous compounds with therapeutic potential. One of them is microcin B17, a bacterial topoisomerase inhibitor whose activity depends on the conversion of selected serine and cysteine residues of the precursor peptide to oxazoles and thiazoles by the McbBCD synthetase complex. Crystal structures of McbBCD reveal an octameric B4C2D2 complex with two bound substrate peptides. Each McbB dimer clamps the N-terminal recognition sequence, while the C-terminal heterocycle of the modified peptide is trapped in the active site of McbC. The McbD and McbC active sites are distant from each other, which necessitates alternate shuttling of the peptide substrate between them, while remaining tethered to the McbB dimer. An atomic-level view of the azole synthetase is a starting point for deeper understanding and control of biosynthesis of a large group of ribosomally synthesized natural products.


Assuntos
Antibacterianos/biossíntese , Proteínas de Bactérias/metabolismo , Bacteriocinas/biossíntese , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Complexos Multienzimáticos/metabolismo , Ribossomos/enzimologia , Inibidores da Topoisomerase II/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Bacteriocinas/química , Bacteriocinas/farmacologia , Sítios de Ligação , Cristalografia por Raios X , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Modelos Moleculares , Complexos Multienzimáticos/química , Complexos Multienzimáticos/genética , Mutação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Estrutura Quaternária de Proteína , Ribossomos/efeitos dos fármacos , Ribossomos/genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/farmacologia , Difração de Raios X
2.
Clin Infect Dis ; 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39378343

RESUMO

The IA-DUET study aimed to compare azole-echinocandin combination with azole monotherapy for invasive aspergillosis. Recruitment was hindered by patient ineligibility, competing studies, and guidelines favoring combination therapy when azole resistance was unknown. The low IA-attributable mortality suggests future trials may benefit from cluster randomization or composite endpoints to enhance efficiency.

3.
Emerg Infect Dis ; 30(8): 1531-1541, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38935978

RESUMO

Azole-resistant Aspergillus fumigatus (ARAf) fungi have been found inconsistently in the environment in Denmark since 2010. During 2018-2020, nationwide surveillance of clinical A. fumigatus fungi reported environmental TR34/L98H or TR46/Y121F/T289A resistance mutations in 3.6% of isolates, prompting environmental sampling for ARAf and azole fungicides and investigation for selection of ARAf in field and microcosmos experiments. ARAf was ubiquitous (20% of 366 samples; 16% TR34/L98H- and 4% TR46/Y121F/T289A-related mechanisms), constituting 4.2% of 4,538 A. fumigatus isolates. The highest proportions were in flower- and compost-related samples but were not correlated with azole-fungicide application concentrations. Genotyping showed clustering of tandem repeat-related ARAf and overlaps with clinical isolates in Denmark. A. fumigatus fungi grew poorly in the field experiment with no postapplication change in ARAf proportions. However, in microcosmos experiments, a sustained complete (tebuconazole) or partial (prothioconazole) inhibition against wild-type A. fumigatus but not ARAf indicated that, under some conditions, azole fungicides may favor growth of ARAf in soil.


Assuntos
Antifúngicos , Aspergillus fumigatus , Azóis , Farmacorresistência Fúngica , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Aspergillus fumigatus/isolamento & purificação , Azóis/farmacologia , Dinamarca/epidemiologia , Antifúngicos/farmacologia , Humanos , Aspergilose/epidemiologia , Aspergilose/microbiologia , Aspergilose/tratamento farmacológico , Testes de Sensibilidade Microbiana , Mutação , Fungicidas Industriais/farmacologia , Genótipo
4.
Emerg Infect Dis ; 30(11): 2323-2332, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39447155

RESUMO

Fluconazole-resistant clade 4 Candida tropicalis causing candidemia in humans has been detected in tropical/subtropical areas, including those in China, Singapore, and Australia. We analyzed 704 individual yeasts isolated from fruits, soil, water, and farmers at 80 orchards in Taiwan. The most common pathogenic yeast species among 251 isolates recovered from farmers were Candida albicans (14.7%) and C. parapsilosis (11.6%). In contrast, C. tropicalis (13.0%), C. palmioleophila (6.6%), and Pichia kudriavzevii (6.0%) were prevalent among 453 environmental isolates. Approximately 18.6% (11/59) of C. tropicalis from the environment were resistant to fluconazole, and 81.8% (9/11) of those belonged to the clade 4 genotype. C. tropicalis susceptibility to fluconazole correlated with susceptibilities to the agricultural azole fungicides, difenoconazole, tebuconazole, and triadimenol. Tandem gene duplications of mutated ERG11 contributed to azole resistance. Agriculture environments are a reservoir for azole-resistant C. tropicalis; discontinuing agricultural use of azoles might reduce emergence of azole-resistant Candida spp. strains in humans.


Assuntos
Antifúngicos , Azóis , Candida tropicalis , Candidemia , Farmacorresistência Fúngica , Genótipo , Testes de Sensibilidade Microbiana , Humanos , Taiwan/epidemiologia , Farmacorresistência Fúngica/genética , Candidemia/microbiologia , Candidemia/epidemiologia , Candida tropicalis/efeitos dos fármacos , Candida tropicalis/genética , Candida tropicalis/isolamento & purificação , Antifúngicos/farmacologia , Azóis/farmacologia , Fluconazol/farmacologia
5.
J Clin Microbiol ; 62(7): e0036924, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38819167

RESUMO

Azole resistance screening in Aspergillus fumigatus sensu stricto can be routinely carried out by using azole-containing agar plates (E.Def 10.2 procedure); however, conidial suspension filtering and inoculum adjustment before inoculum preparation are time-consuming. We evaluated whether skipping the filtration and inoculum adjustment steps negatively influenced the performance of the E.Def 10.2 procedure. A. fumigatus sensu stricto isolates (n = 98), previously classified as azole susceptible or azole resistant (E.Def 9.4 method), were studied. Azole-resistant isolates had either the wild-type cyp51A gene sequence (n = 1) or the following cyp51A gene substitutions: TR34-L98H (n = 41), G54R (n = 5), TR46-Y121F-T289A (n = 1), or G448S (n = 1). In-house azole-containing agar plates were prepared according to the EUCAST E.Def 10.2 procedure. Conidial suspensions obtained by adding distilled water (Tween 20 0.1%) were either filtered and the inocula adjusted to 0.5 McFarland or left unfiltered and unadjusted. Agreements between the agar screening methods using inocula prepared by each procedure were high for itraconazole (99%), voriconazole (100%), and posaconazole (94.9%). Sensitivity and specificity (considering the susceptibility category as per the microdilution E.Def 9.4 method as the gold standard) of E.Def 10.2 were 100% to rule in or rule out resistance when unfiltered and unadjusted suspensions were used; the resistance phenotype of isolates harboring the TR34-L98H, G54R, or TR46-Y121F-T289A substitutions was correctly detected. Unfiltered and unadjusted conidial suspensions do not negatively influence the performance of the E.Def 10.2 method when screening for azole resistance in A. fumigatus sensu stricto. IMPORTANCE: Azole resistance screening in Aspergillus fumigatus sensu stricto can be routinely carried out by using azole-containing plates (E.Def 10.2 procedure); however, conidial suspension filtering and inoculum adjustment before inoculation of plates are time-consuming. We, here, showed that unfiltered and unadjusted conidial suspensions do not negatively influence the performance of the E.Def 10.2 method when screening for azole resistance in A. fumigatus sensu stricto.


Assuntos
Antifúngicos , Aspergillus fumigatus , Azóis , Farmacorresistência Fúngica , Testes de Sensibilidade Microbiana , Esporos Fúngicos , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Aspergillus fumigatus/isolamento & purificação , Azóis/farmacologia , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana/métodos , Humanos , Esporos Fúngicos/efeitos dos fármacos , Esporos Fúngicos/genética , Meios de Cultura/química , Proteínas Fúngicas/genética , Ágar , Sistema Enzimático do Citocromo P-450/genética
6.
Appl Environ Microbiol ; 90(4): e0001724, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38534143

RESUMO

The emergence of azole-resistant Aspergillus fumigatus (ARAf) across the world is an important public health concern. We sought to determine if propiconazole, a demethylase inhibitor (DMI) fungicide, exerted a selective pressure for ARAf in a tomato production environment following multiple exposures to the fungicide. A tomato field trial was established in 2019 and propiconazole was applied weekly until harvest. Soil, leaf, and fruit (when present) samples were collected at baseline and after each propiconazole application. A. fumigatus isolates (n, 178) were recovered and 173 were tested for susceptibility to itraconazole, posaconazole, voriconazole, and propiconazole in accordance with CLSI M38 guidelines. All the isolates were susceptible to medical triazoles and the propiconazole MIC ranged from 0.25 to 8 mg/L. A linear regression model was fitted that showed no longitudinal increment in the log2-fold azole MIC of the isolates collected after each propiconazole exposure compared to the baseline isolates. AsperGenius real-time multiplex assay ruled out TR34/L98H and TR46/Y121F/T289A cyp51A resistance markers in these isolates. Sequencing of a subset of isolates (n, 46) demonstrated widespread presence of F46Y/M172V/E427K and F46Y/M172V/N248T/D255E/E427K cyp51A mutations previously associated with reduced susceptibility to triazoles. IMPORTANCE: The agricultural use of azole fungicides to control plant diseases has been implicated as a major contributor to ARAf infections in humans. Our study did not reveal imposition of selection pressure for ARAf in a vegetable production system. However, more surveillance studies for ARAf in food crop production and other environments are warranted in understanding this public and One Health issue.


Assuntos
Fungicidas Industriais , Solanum lycopersicum , Humanos , Aspergillus fumigatus/genética , Azóis/farmacologia , Antifúngicos/farmacologia , Proteínas Fúngicas/genética , Farmacorresistência Fúngica/genética , Triazóis/farmacologia , Fungicidas Industriais/farmacologia , Verduras , Testes de Sensibilidade Microbiana
7.
Chemistry ; : e202402843, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39304988

RESUMO

The utilization of axially chiral biaryl diamines has been widely acknowledged as highly advantageous structures for the advancement of chiral catalysts and ligands. This highlights their extensive range of applications in asymmetric catalysis and synthesis. Herein, we devised a direct arylation reactions of 5-aminopyrazoles with azonaphthalenes, utilizing chiral phosphoric acid as the catalyst. This method delivers structurally novel atroposelective N, N-1,2-azole heteroaryl diamines with high yields (up to >98%) and good to excellent enantiomeric ratios while exhibiting a wide range of substrate compatibility.

8.
Arch Microbiol ; 206(7): 305, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878211

RESUMO

Aspergillus fumigatus is a ubiquitous filamentous fungus commonly found in the environment. It is also an opportunistic human pathogen known to cause a range of respiratory infections, such as invasive aspergillosis, particularly in immunocompromised individuals. Azole antifungal agents are widely used for the treatment and prophylaxis of Aspergillus infections due to their efficacy and tolerability. However, the emergence of azole resistance in A. fumigatus has become a major concern in recent years due to their association with increased treatment failures and mortality rates. The development of azole resistance in A. fumigatus can occur through both acquired and intrinsic mechanisms. Acquired resistance typically arises from mutations in the target enzyme, lanosterol 14-α-demethylase (Cyp51A), reduces the affinity of azole antifungal agents for the enzyme, rendering them less effective, while intrinsic resistance refers to a natural resistance of certain A. fumigatus isolates to azole antifungals due to inherent genetic characteristics. The current review aims to provide a comprehensive overview of azole antifungal resistance in A. fumigatus, discusses underlying resistance mechanisms, including alterations in the target enzyme, Cyp51A, and the involvement of efflux pumps in drug efflux. Impact of azole fungicide uses in the environment and the spread of resistant strains is also explored.


Assuntos
Antifúngicos , Aspergilose , Aspergillus fumigatus , Azóis , Farmacorresistência Fúngica , Proteínas Fúngicas , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Azóis/farmacologia , Farmacorresistência Fúngica/genética , Antifúngicos/farmacologia , Humanos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Aspergilose/microbiologia , Aspergilose/tratamento farmacológico , Testes de Sensibilidade Microbiana , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Mutação
9.
Med Mycol ; 62(7)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38769604

RESUMO

Azole resistance in Aspergillus fumigatus (ARAf) is becoming a worldwide health threat due to increasing occurrence in the environment. However, environmental surveillance programs are not commonly in place and are lacking in Belgium. Since no data on the occurrence of ARAf and the presence of hotspots for the selection of azole resistance is available in Belgium, a first study on the prevalence of ARAf in the environment was conducted. A total of 232 air and compost or soil samples were taken from two composting facilities, and from horticultural and agricultural crops. The azole susceptibility pattern was determined using the EUCAST method (E. Def. 9.4), and the cyp51A gene and its promotor region were sequenced in A. fumigatus isolates with phenotypic azole resistance. Six pan-azole-resistant A. fumigatus isolates were identified, originating from compost and horticultural crops. Four isolates carried the TR34/L98H mutation, and one isolate carried the TR46/Y121F/T289A mutation. However, we did not observe any ARAf isolates from agricultural crops. In conclusion, this study reported the first TR34/L98H and TR46/Y121F/T289A mutation isolated from a composting facility and horticulture in Belgium. The implementation of standardization in environmental surveillance of A. fumigatus on a European level would be beneficial in order to identify hotspots.


The ubiquitous fungus Aspergillus fumigatus can cause serious invasive diseases in humans. Due to the extensive use of environmental azoles, an increase of clinical infections with azole-resistant A. fumigatus is seen. This pilot study aimed to estimate the prevalence of azole-resistant A. fumigatus in environmental reservoirs in Belgium.


Assuntos
Antifúngicos , Aspergillus fumigatus , Azóis , Compostagem , Farmacorresistência Fúngica , Proteínas Fúngicas , Bélgica , Aspergillus fumigatus/genética , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/isolamento & purificação , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Azóis/farmacologia , Antifúngicos/farmacologia , Testes de Sensibilidade Microbiana , Microbiologia do Solo , Mutação , Sistema Enzimático do Citocromo P-450/genética
10.
Med Mycol ; 62(4)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38490745

RESUMO

The prevalence of azole-resistant Aspergillus fumigatus is increasing worldwide and is speculated to be related to the use of azole pesticides. Aspergillus spp., the causative agent of aspergillosis, could be brought into domestic dwellings through food. However, studies on azole-resistant Aspergillus spp. in food products are limited. Therefore, we aimed to isolate Aspergillus spp. from processed foods and commercial agricultural products and performed drug susceptibility tests for azoles. Among 692 food samples, we isolated 99 strains of Aspergillus spp. from 50 food samples, including vegetables (22.9%), citrus fruits (26.3%), cereals (25.5%), and processed foods (1.8%). The isolates belonged to 18 species across eight sections: Aspergillus, Candidi, Clavati, Flavi, Fumigati, Nidulantes, Nigri, and Terrei. The most frequently isolated section was Fumigati with 39 strains, followed by Nigri with 28 strains. Aspergillus fumigatus and A. welwitschiae were the predominant species. Ten A. fumigatus and four cryptic strains, four A. niger cryptic strains, two A. flavus, and four A. terreus strains exceeded epidemiological cutoff values for azoles. Aspergillus tubingensis, A. pseudoviridinutans, A. lentulus, A. terreus, and N. hiratsukae showed low susceptibility to multi-azoles. Foods containing agricultural products were found to be contaminated with Aspergillus spp., with 65.3% of isolates having minimal inhibitory concentrations below epidemiological cutoff values. Additionally, some samples harbored azole-resistant strains of Aspergillus spp. Our study serves as a basis for elucidating the relationship between food, environment, and clinically important Aspergillus spp.

11.
Med Mycol ; 62(4)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38521982

RESUMO

Our understanding of fungal epidemiology and the burden of antifungal drug resistance in COVID-19-associated candidemia (CAC) patients is limited. Therefore, we conducted a retrospective multicenter study in Iran to explore clinical and microbiological profiles of CAC patients. Yeast isolated from blood, were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and subjected to antifungal susceptibility testing (AFST) using the broth microdilution method M27-A3 protocol. A total of 0.6% of the COVID-19 patients acquired CAC (43/6174). Fluconazole was the most widely used antifungal, and 37% of patients were not treated. Contrary to historic candidemia patients, Candida albicans and C. tropicalis were the most common species. In vitro resistance was high and only noted for azoles; 50%, 20%, and 13.6% of patients were infected with azole-non-susceptible (ANS) C. tropicalis, C. parapsilosis, and C. albicans isolates, respectively. ERG11 mutations conferring azole resistance were detected for C. parapsilosis isolates (Y132F), recovered from an azole-naïve patient. Our study revealed an unprecedented rise in ANS Candida isolates, including the first C. parapsilosis isolate carrying Y132F, among CAC patients in Iran, which potentially threatens the efficacy of fluconazole, the most widely used drug in our centers. Considering the high mortality rate and 37% of untreated CAC cases, our study underscores the importance of infection control strategies and antifungal stewardship to minimize the emergence of ANS Candida isolates during COVID-19.


Assuntos
COVID-19 , Candidemia , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candidemia/tratamento farmacológico , Candidemia/epidemiologia , Candidemia/microbiologia , Candidemia/veterinária , Fluconazol/uso terapêutico , Azóis/farmacologia , Azóis/uso terapêutico , Testes de Sensibilidade Microbiana/veterinária , COVID-19/epidemiologia , COVID-19/veterinária , Candida , Candida albicans , Candida tropicalis , Candida parapsilosis , Farmacorresistência Fúngica
12.
Med Mycol ; 62(10)2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39327022

RESUMO

Azole resistance has emerged as a new therapeutic challenge in patients with aspergillosis. Various resistance mutations are attributed to the widespread use of triazole-based fungicides in agriculture. This study explored the prevalence of azole-resistant Aspergillus fumigatus (ARAF) and other aspergilli in the Argentine environment. A collection of A. fumigatus and other aspergilli strains isolated from soil of growing crops, compost, corn, different animal feedstuffs, and soybean and chickpea seeds were screened for azole resistance. No ARAF was detected in any of the environmental samples studied. However, five A. flavus, one A. ostianus, one A. niger and one A. tamarii recovered from soybean and chickpea seeds showed reduced susceptibility to medical azole antifungals (MAA). The susceptibility profiles of five A. flavus isolates, showing reduced susceptibility to demethylase inhibitors (DMIs), were compared with those of 10 isolates that exhibited susceptibility to MAA. Aspergillus flavus isolates that showed reduced MAA susceptibility exhibited different susceptibility profiles to DMIs. Prothioconazole and tebuconazole were the only DMIs significantly less active against isolates with reduced susceptibility to MAA. Although no ARAF isolates were found in the samples analysed, other aspergilli with reduced susceptibility profile to MAA being also important human pathogens causing allergic, chronic and invasive aspergillosis, are present in the environment in Argentina. Although a definitive link between triazole-based fungicide use and isolation of azole-resistant human pathogenic aspergilli from agricultural fields in Argentina remains elusive, this study unequivocally highlights the magnitude of the environmental spread of azole resistance among other Aspergillus species.


This study intended to inform about the prevalence of Aspergillus species showing triazole resistance in the Argentinian environment. Since azole fungicides are used for crop protection, it was expected that azole resistance in this species with cross-resistance to medical azoles could occur.


Assuntos
Antifúngicos , Azóis , Farmacorresistência Fúngica , Testes de Sensibilidade Microbiana , Argentina/epidemiologia , Azóis/farmacologia , Antifúngicos/farmacologia , Prevalência , Microbiologia Ambiental , Microbiologia do Solo , Aspergillus/efeitos dos fármacos , Aspergillus/isolamento & purificação , Aspergillus/genética , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Aspergillus fumigatus/isolamento & purificação , Humanos , Aspergilose/microbiologia , Aspergilose/epidemiologia
13.
Med Mycol ; 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39479789

RESUMO

We evaluated the combined performance of itraconazole and voriconazole Etest® gradient concentration strips for detecting A. fumigatus azole resistance associated with cyp51a mutations confirmed by gene sequencing. Among 118 Aspergillus fumigatus clinical isolates collected in a French center, 6 (5%) had azole resistance mutations, 5 of which were probably of environmental origin. Using recent method-dependent Epidemiological Cut-Off Values (ECVs) as thresholds, the combination's sensitivity and specificity were 100% [95% confidence interval 61-100] and 99% [95-100]. Our results support itraconazole and voriconazole Etest® combined use as a promising self-sufficient method for simple, efficient and reliable cyp51a-related azole resistant A fumigatus detection.


Azole resistance in Aspergillus fumigatus is mainly due to mutations in the cyp51a gene and is a challenge for laboratory detection and therapeutic management. We evaluated a combination of two Etest® strips as a simple screening method by evaluating its results in concordance with gene sequencing.

14.
Pediatr Blood Cancer ; 71(2): e30782, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37990039

RESUMO

Erratic absorption of posaconazole oral suspension necessitates frequent dosing and administration with meals or supplements. Alternative enteral formulations are desirable for patients intolerant to enteral nutrition. Crushed posaconazole delayed-release tablets (POS-DRT) show promise in adults; limited evidence exists in children. We used crushed POS-DRT in 10 encounters with nine pediatric patients, achieving target POS concentrations in 90% of encounters. This highlights crushed POS-DRT as a potential enteral option for pediatric antifungal prophylaxis and treatment.


Assuntos
Antifúngicos , Adulto , Humanos , Criança , Antifúngicos/uso terapêutico , Estudos Retrospectivos , Administração Oral , Comprimidos
15.
Infection ; 52(5): 1651-1656, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38801514

RESUMO

OBJECTIVES: We aimed to report the emergence of azole-resistant invasive aspergillosis in hematologic patients admitted to a tertiary hospital in Spain during the last 4 months. METHODS: Prospective, descriptive study was performed to describe and follow all consecutive proven and probable invasive aspergillosis resistant to azoles from hematological cohort during the last 4 months. All patients had fungal cultures and antifungal susceptibility or real-time PCR detection for Aspergillus species and real-time PCR detection for azole-resistant mutation. RESULTS: Four cases of invasive aspergillosis were diagnosed in 4 months. Three of them had azole-resistant aspergillosis. Microbiological diagnosis was achieved in three cases by means of fungal culture isolation and subsequent antifungal susceptibility whereas one case was diagnosed by PCR-based aspergillus and azole resistance detection. All the azole-resistant aspergillosis presented TR34/L98H mutation. Patients with azole-resistant aspergillosis had different hematologic diseases: multiple myeloma, lymphoblastic acute leukemia, and angioimmunoblastic T lymphoma. Regarding risk factors, one had prolonged neutropenia, two had corticosteroids, and two had viral co-infection. Two of the patients developed aspergillosis under treatment with azoles. CONCLUSION: We have observed a heightened risk of azole-resistant aspergillosis caused by A. fumigatus harboring the TR34/L98H mutation in patients with hematologic malignancies. The emergence of azole-resistant aspergillosis raises concerns for the community, highlighting the urgent need for increased surveillance and the importance of susceptibility testing and new drugs development.


Assuntos
Antifúngicos , Aspergilose , Aspergillus fumigatus , Azóis , Farmacorresistência Fúngica , Mutação , Humanos , Espanha/epidemiologia , Farmacorresistência Fúngica/genética , Azóis/farmacologia , Azóis/uso terapêutico , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/genética , Aspergillus fumigatus/isolamento & purificação , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Masculino , Feminino , Pessoa de Meia-Idade , Aspergilose/microbiologia , Aspergilose/tratamento farmacológico , Idoso , Estudos Prospectivos , Adulto , Testes de Sensibilidade Microbiana , Neoplasias Hematológicas/complicações
16.
Bioorg Med Chem ; 114: 117947, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39418748

RESUMO

The World Health Organization (WHO) recognizes Candida albicans and Cryptococcus neoformans as the critical priority fungal pathogens for which therapeutic solutions are needed. Azole-based antifungal agents, including triazoles, diazoles, and thiazoles, are widely used in the treatments for fungal infections. In light of past successes in the transformation of antibacterial kanamycin into antifungal derivatives via chemical modifications, a new library of kanamycin-azole hybrids was synthesized and tested against a panel of azole-resistant and susceptible Candida and Cryptococcus strains. Structure activity relationship (SAR) studies revealed pivotal roles for antifungal activity of the azole ring (imidazole vs triazole) and halogen substituents on the benzene ring (F vs Cl). Most notably, hybrids 13, 14 and 15 were active against resistant C. albicans, C. tropicalis and C. neoformans strains and non-toxic towards mammalian cells. Mode of action investigations using fluorogenic dyes, (SYTOXTM) showed the fungal active compounds could permeabilize fungal membranes even at » MICs. These findings reveal novel azole-based antifungals that could offer new therapeutic options for candidiasis and cryptococcosis.


Assuntos
Antifúngicos , Azóis , Cryptococcus neoformans , Canamicina , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Relação Estrutura-Atividade , Canamicina/farmacologia , Canamicina/química , Canamicina/síntese química , Cryptococcus neoformans/efeitos dos fármacos , Azóis/química , Azóis/farmacologia , Azóis/síntese química , Candida albicans/efeitos dos fármacos , Candida/efeitos dos fármacos , Estrutura Molecular , Humanos , Relação Dose-Resposta a Droga
17.
Bioorg Med Chem ; 97: 117543, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38071944

RESUMO

In order to develop antifungal drugs, a series of novel azole analogues were designed and synthesized based on our previous work. Most of the target compounds had broad-spectrum antifungal activity, which showed excellent to moderate inhibitory activity against the tested strains, except A. fum 0504656. Among these, compounds B3, B7, B8, B11, B12 and E9 showed excellent activity against C. alb Y0109 and C. alb SC5314 (with the MIC80: 0.0156 ug/mL). In addition, compound B3 showed the best inhibitory activity against fluconazole-resistant strains C. alb 901 and C. alb 904, and had low toxicity against NIH/3T3 cells at the effective MIC range against fungi. Structure-activity relationship and docking studies of the derivatives suggest that the presence of the 2-fluoro-4-hydroxyphenyl and 1,2,3-triazole group enhance the antifungal activity of the compounds, which may be related to the interaction of the key groups with the amino acids surrounding the target enzyme.


Assuntos
Antifúngicos , Azóis , Animais , Camundongos , Antifúngicos/química , Azóis/farmacologia , Candida albicans , Testes de Sensibilidade Microbiana , Fluconazol/farmacologia , Relação Estrutura-Atividade
18.
Transpl Infect Dis ; : e14379, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39312268

RESUMO

BACKGROUND: Coccidioidomycosis may cause severe disseminated disease and mortality among lung transplant recipients. A strategy of lifelong azole prophylaxis was previously associated with low rates of coccidioidomycosis. Whether lung transplant recipients relocating to the Coccidioides endemic region are also at risk and would benefit from antifungal prophylaxis is unknown. METHODS: Lung transplant recipients transplanted at an outside center with low Coccidioides endemicity before relocating for post-transplant follow-up at a transplant center in Phoenix, Arizona from January 2013 to March 2024 were included. The primary outcome was proven or probable coccidioidomycosis per Mycoses Study Group consensus definitions. RESULTS: Forty lung transplant recipients were included, with 62.5% not receiving antifungal prophylaxis at the time of transfer. The median time from transplant to relocation was 34 months. Of those not on prophylaxis, 96% were initiated on azole therapy at the first clinic visit, with 72% prescribed itraconazole. Coccidioides serologic testing was performed in 30% of the cohort, most often in the context of a broad diagnostic work-up for suspected infection during hospitalization. After a median follow-up of 31 months, one case (2.5%) of proven pulmonary coccidioidomycosis was identified, occurring 4.8 years post-transplant and >2 years post-transfer in a cystic fibrosis patient who had a pause in fluconazole prophylaxis for >1 month prior to diagnosis due to gastrointestinal intolerance and access issues. The patient was treated and maintained on isavuconazole without complications. CONCLUSION: Azole antifungal prophylaxis was associated with a low rate of coccidioidomycosis among lung transplant recipients relocating to the highly endemic region.

19.
Transpl Infect Dis ; 26(1): e14209, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38059638

RESUMO

The triazole antifungal isavuconazole (ISAVU) is used for prevention and treatment of fungal infections in solid organ transplant (SOT). SOT recipients commonly need to transition from one azole to another due to breakthrough infection, toxicity, or other reasons. The purpose of our study was to evaluate the effect of ISAVU on immunosuppressant concentrations in thoracic transplant recipients when ISAVU was started de novo or transitioned from another azole. We conducted a single-center retrospective cohort study including 68 patients (51 lung, 14 heart, and 3 heart/lung transplant). Concentration to dosage ratios (C/D) of immunosuppressants were assessed at baseline, day 3, and weekly for 9 weeks. When starting ISAVU de novo, we observed a temporary doubling of tacrolimus exposure. Cyclosporine and sirolimus required dose decreases. Tacrolimus C/D increased by 110% at day 3 in patients started on ISAVU de novo then returned to baseline C/D ± 17% weeks 2-9 (n = 8). One cyclosporine patient started on ISAVU de novo had variable C/D, and C/D increased by 219% ± 72% in 2 sirolimus patients. When transitioning from other azoles, tacrolimus and cyclosporine required about twice the initial dose. After week 1, tacrolimus C/D decreased by 53% ± 6% in patients transitioned from posaconazole (n = 33), voriconazole (n = 14), or fluconazole (n = 2). Cyclosporine C/D decreased by 45% ± 16% in patients transitioning from other azoles (posaconazole [n = 2], voriconazole [n = 2], fluconazole [n = 1]). Sirolimus C/D decreased by 73% ± 13% in patients transitioned from posaconazole (n = 7). Aside from the initial loading phase, ISAVU had a lesser degree of interaction with immunosuppressants than other azoles in loading phase, ISAVU had a lesser degree of interaction with immunosuppressants than other azoles in adjustments for the 4-week period after initiating antifungal therapy with ISAVU or switching from another agent.


Assuntos
Azóis , Imunossupressores , Nitrilas , Piridinas , Humanos , Imunossupressores/efeitos adversos , Azóis/uso terapêutico , Antifúngicos/efeitos adversos , Tacrolimo/uso terapêutico , Voriconazol/uso terapêutico , Fluconazol , Transplantados , Estudos Retrospectivos , Triazóis/efeitos adversos , Ciclosporina , Sirolimo
20.
Mol Divers ; 28(1): 61-71, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36609739

RESUMO

An efficient visible light mediated, eosin Y catalyzed direct C-H oxidative amination of benzoxazoles with secondary amines has been developed, which providing a straightforward, green, and environmentally benign access to a wide variety of substituted benzoxazole-2-amines under mild reaction conditions. The biological studies such as drug-likeness and molecular docking are also carried out on the molecule.


Assuntos
Aminas , Benzoxazóis , Aminação , Simulação de Acoplamento Molecular , Catálise , Estrutura Molecular , Metais , Luz
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