Exposure to resistant fungi across working environments and time

Antifungal resistance has emerged as a significant health concern with increasing reports of resistant variants in previously susceptible species. At present, little is known about occupational exposure to antifungal-resistant fungi. This study aimed to investigate Danish workers' occupational exposure to airborne fungi resistant to first-line treatment drugs. A retrospective study was performed on a unique collection of personal exposure samples gathered over a twenty-year period from Danish working environments, in sectors including agriculture, animal handling, waste management, and healthcare. A total of 669 samples were cultivated at 37 °C and fungal colonies were identified using MALDI-TOF MS. Subsequently, identification was confirmed by amplicon sequencing the genes of calmodulin and beta-tubulin to unveil potential cryptic species. Infectious fungi (495 isolates from 23 species) were tested for resistance against Itraconazole, Voriconazole, Posaconazole, and Amphotericin B. Working environments were highly variable in the overall fungal exposure, and showed vastly different species compositions. Resistance was found in 30 isolates of the species Aspergillus fumigatus (4 of 251 isolates), A. nidulans (2 of 13), A. niger complex (19 of 131), A. versicolor (3 of 18), and A. lentulus (2 of 2). Sequence analysis revealed several cryptic species within the A. niger complex including A. tubingensis, A. luchuensis, and A. phoenicis. Among the resistant A. fumigatus isolates, two contained the well-described TR34/L98H mutation in the cyp51A gene and promoter region, while the remainder harbored silent mutations. The results indicate that the working environment significantly contributes to exposure to resistant fungi, with particularly biofuel plant workers experiencing high exposure. Differences in the prevalence of resistance across working environments may be linked to the underlying species composition.

Sulfur (SⅥ)-containing heterocyclic hybrids as antibacterial agents against methicillin-resistant Staphylococcus aureus (MRSA) and its SAR

The discovery of new small molecule-based inhibitors is an attractive field in medicinal chemistry. Structurally diversified heterocyclic derivatives have been investigated to combat multi-drug resistant bacterial infections and they offers several mechanism of action. Methicillin-resistant Staphylococcus aureus (MRSA) is becoming more and more deadly to humans because of its simple method of transmission, quick development of antibiotic resistance, and ability to cause hard-to-treat skin and filmy diseases. The sulfur (SVI) particularly sulfonyl and sulfonamide based heterocyclic moieties, have found to be good anti-MRSA agents. The development of new nontoxic, economical and highly active sulfur (SVI) containing derivatives has become hot research topics in drug discovery research. Presently, more than 150 FDA approved Sulfur (SVI)-based drugs are available in the market, and they are widely used to treat various types of diseases with different therapeutic potential. The present collective data provides the latest advancements in Sulfur (SVI)-hybrid compounds as antibacterial agents against MRSA. It also examines the outcomes of in-vitro and in-vivo investigations, exploring potential mechanisms of action and offering alternative perspectives on the structure-activity relationship (SAR). Sulfur (SVI)-hybrids exhibits synergistic effects with existing drugs to provide antibacterial action against MRSA.

Azoles display promising anticonvulsant effects through possible PPAR-α activation

Azoles such as nafimidone, denzimol and loreclezole are known for their clinical efficacy against epilepsy, and loreclezole acts by potentiating γ-aminobutyric acid (GABA)-ergic currents. In the current study, we report a series of azole derivatives in alcohol ester and oxime ester structure showing promising anticonvulsant effects in 6 Hz and maximal electro shock (MES) models with minimal toxicity. The most promising of the series, 5f, was active in both 6 Hz and MES tests with a median effective dose (ED50) of 118.92 mg/kg in 6 Hz test and a median toxic dose (TD50) twice as high in mice. The compounds were predicted druglike and blood-brain barrier (BBB) penetrant in silico. Contrary to what was expected, the compounds showed no in vitro affinity to GABAA receptors (GABAARs) in radioligand binding assays; however, they were found structurally similar to peroxisome proliferator-activated receptors alpha (PPAR-α) agonists and predicted to show high affinity and agonist-like binding to PPAR-α in molecular docking studies. As a result, 5f emerged as a safe azole anticonvulsant with a wide therapeutic window and possible action through PPAR-α activation.

Malassezia dermatitis in dogs and cats

Malassezia are members of the mycobiome of dogs and cats. In the presence of an underlying disease, these yeasts can proliferate, attach to the skin or mucosa to induce a secondary Malassezia dermatitis, otitis externa or paronychia. Since allergic dermatitis is one of the most common underlying causes, diagnostic investigation for allergy is often indicated. Cats may suffer from various other underlying problems, especially where Malassezia dermatitis is generalised. Malassezia dermatitis in dogs and cats is chronic, relapsing and pruritic. Direct cytology from dermatological lesions and the ear canal, showing "peanut-shaped" budding yeasts, facilitates a rapid and reliable diagnosis. Topical treatment includes antiseptic and antifungal azole-based products. Systemic treatment with oral antifungals is indicated only in severe or refractory disease. Identification and treatment of the underlying cause is essential for an optimal response. In this evidence-based narrative review, we discuss the clinical presentation of Malassezia dermatitis in dogs and cats, underlying comorbidities, and diagnostic considerations. Treatment is discussed in light of emerging evidence of antifungal resistance and the authors' clinical experience.

Clinical evaluation of antifungal de-escalation in Candida infections: A systematic review and meta-analysis

OBJECTIVES

De-escalation (DES) from echinocandins to azoles is recommended by several medical societies in Candida infections. We summarise the evidence of DES on clinical and microbiological cure and 30-day survival and compare it with continuing the treatment with echinocandins (non-DES).

METHODS

We searched MEDLINE, Embase, Web of Science and Scopus. Studies describing DES in inpatients and reporting any of the outcomes evaluated were included. Pooled estimates of the tree outcomes were calculated with a fixed or random-effects model. Heterogeneity was explored stratifying by subgroups and via meta-regression. This systematic review is registered with PROSPERO (CRD42023475486).

RESULTS

Of 1853 records identified, 9 studies were included, totalling 1575 patients. Five studies stepped-down to fluconazole; one to voriconazole and three to any of azoles. The mean day of DES was 5.2 (4.6-6.5) days. The clinical cure OR was 1.29 (95% CI: 0.88-1.88); the microbiological cure 1.62 (95% CI: 0.71-3.71); and 30-day survival 2.17 (95% CI: 1.09-4.32). The 30-day survival data into subgroups showed higher effect on critically ill patients and serious-risk bias studies. Meta-regression did not identify significant effect modifiers.

CONCLUSIONS

DES is a safe strategy; it showed no higher 30-day mortality and a trend towards greater clinical and microbiological cure.

Thiadiazole-, selenadiazole- and triazole-fused anthraquinones as G-quadruplex targeting anticancer compounds

G-quadruplex (G4) ligands attract considerable attention as potential anticancer therapeutics. In this study we proposed an original scheme for synthesis of azole-fused anthraquinones and prepared a series of G4 ligands carrying amino- or guanidinoalkylamino side chains. The heterocyclic core and structure of the terminal groups strongly affect on binding to G4-forming oligonucleotides, cellular accumulation and antitumor potency of compounds. In particular, thiadiazole- and selenadiazole- but not triazole-based ligands inhibit the proliferation of tumor cells (e.g. K562 leukemia) and stabilize primarily telomeric and c-MYC G4s. Anthraselenadiazole derivative 11a showed a good affinity to c-MYC G4 in vitro and down-regulated expression of c-MYC oncogene in cellular conditions. Further studies revealed that anthraselenadiazole 11a provoked cell cycle arrest and apoptosis in a dose- and time-dependent manner inhibiting K562 cells growth. Taken together, this work gives a valuable example that the closely related heterocycles may cause a significant difference in biological properties of G4 ligands.

A Review on Pyrazole Derivatives Used in the Treatment of Rheumatoid Arthritis: Recent Advancement and Drug Development

Rheumatoid arthritis (RA) is an autoimmune disorder where inflammation and destruc-tion of bone are the hallmarks of the disease. This review focuses on the etiology, pathophysiolo-gy, and treatment strategies for RA, along with the different approaches used for the synthesis of pyrazoles, the characterization of various properties, and their biological significance for curing RA. The activated immune system of the body causes inflammation of the synovial joint due to the interaction of immune cells, such as T and B lymphocytes, macrophages, plasma cells, den-dritic cells and mast cells. The treatment for RA has been revolutionized with the discovery of new chemical compounds and an understanding of their mechanism in the treatment of the dis-ease. Pyrazoles are the starting materials for the synthesis of heterocyclic compounds and possess great relevance in the pharmaceutical field for the development of new drugs. They are versatile bio-scaffolds in medicinal chemistry and organic synthesis. This has been followed by a deep analysis of pyrazoles and their derivatives on the basis of medical significance in the treatment of RA. This follow-up and information may help the chemists, scientists, and researchers to generate new pyrazole compounds with high efficacy for better treatment of patients with RA. We summa-rize the review with an understanding of the core of pyrazoles and a claim that their derivatives may be helpful in the development of efficient drugs against RA.

Impaired spermatogenesis and associated endocrine effects of azole fungicides in peripubertal Xenopus tropicalis

Early life exposure to endocrine disrupting chemicals (EDCs) has been suggested to adversely affect reproductive health in humans and wildlife. Here, we characterize endocrine and adverse effects on the reproductive system after juvenile exposure to propiconazole (PROP) or imazalil (IMZ), two common azole fungicides with complex endocrine modes of action. Using the frog Xenopus tropicalis, two short-term (2-weeks) studies were conducted. I: Juveniles (2 weeks post metamorphosis (PM)) were exposed to 0, 17 or 178 µg PROP/L. II: Juveniles (6 weeks PM) were exposed to 0, 1, 12 or 154 µg IMZ/L. Histological analysis of the gonads revealed an increase in the number of dark spermatogonial stem cells (SSCs)/testis area, and in the ratio secondary spermatogonia: dark SSCs were increased in all IMZ groups compared to control. Key genes in gametogenesis, retinoic acid and sex steroid pathways were also analysed in the gonads. Testicular levels of 3β-hsd, ddx4 were increased and cyp19 and id4 levels were decreased in the IMZ groups. In PROP exposed males, increased testicular aldh1a2 levels were detected, but no histological effects observed. Although no effects on ovarian histology were detected, ovarian levels of esr1, rsbn1 were increased in PROP groups, and esr1 levels were decreased in IMZ groups. In conclusion, juvenile azole exposure disrupted testicular expression of key genes in retinoic acid (PROP) and sex steroid pathways and in gametogenesis (IMZ). Our results further show that exposure to environmental concentrations of IMZ disrupted spermatogenesis in the juvenile testis, which is a cause for concern as it may lead to impaired fertility. Testicular levels of id4, ddx4 and the id4:ddx4 ratio were associated with the number of dark SSCs and secondary spermatogonia suggesting that they may serve as a molecular markers for disrupted spermatogenesis.

Dearomative Insertion of Fluoroalkyl Carbenes into Azoles Leading to Fluoroalkyl Heterocycles with a Quaternary Center

The skeletal ring expansion of heteroarenes through carbene insertion is gaining popularity in synthetic chemistry. Efficient strategies for heterocyclic ring expansion to access heterocycles containing a fluoroalkyl quaternary carbon center through fluoroalkyl carbene insertion are highly desirable because of their broad applications in medicinal chemistry. Herein, we report a general strategy for the dearomative one-carbon insertion of azoles using fluoroalkyl N-triftosylhydrazones as fluoroalkyl carbene precursors, resulting in ring-expanded heterocycles in excellent yields with good functional-group compatibility. The broad generality of this methodology in the late-stage diversification of pharmaceutically interesting bioactive molecules and versatile transformations of the products has been demonstrated.

Epidemiology and antifungal susceptibility of fungal infections from 2018 to 2021 in Shandong, eastern China: A report from the SPARSS program

PURPOSE

We analyzed the pathogenic fungal epidemiology and antifungal susceptibility from 2018 to 2021 in Shandong Province, China, to provide the basis for empiric antifungal therapy.

METHODS

Fungal isolates were collected from 54 hospitals in Shandong province from 2018 to 2021 through the Shandong Province Pediatric bacterial & fungal Antimicrobial Resistance Surveillance System (SPARSS), WHONET v5.6 and SPSS software v20.0 were used for statistical analysis.

RESULTS

A total of 15,348 strains of fungi were collected, with Candida accounting for 78.25 %, followed by Aspergillus at 15.45 %, and other species at 6.27 %. Candida albicans was the predominant Candida species, but more than half of the Candida isolates were non-albicans species, with C. tropicalis being the most dominant (22.74 %), followed by C. glabrata (17.50 %) and C. parapsilosis (11.02 %). The composition of fungi varied significantly among different age groups. Children had a higher proportion of C. albicans (47.30 %) compared to non-children (32.06 %). The non-wild-type phenotype rate of Candida for Amphotericin B was less than 3 %, while Cryptococcus neoformans was 16.67 %. In addition, less than 6 % of C. albicans and C. parapsilosis were resistant to fluconazole and voriconazole, and 96.30 % of C. glabrata were SDD to fluconazole. We also found that 80.56 % of C. glabrata and 83.70 % of C. krusei were voriconazole WT/susceptibility phenotype. However, the susceptibility rates of C. tropicalis to fluconazole/voriconazole decreased from 70.40 %/46.40 % in 2018 to 62.30 %/35.20 % in 2021. The comprehensive susceptibility rate to fluconazole of C. albicans, C. tropicalis, C. parapsilosis and C. glabrata isolated from the blood has decreased from 69.36 % to 56.62 %.

CONCLUSIONS

The study reveals that the composition and antifungal susceptibility of pathogenic fungi in Shandong Province differ from other regions. Moreover, the resistance to azoles is more severe, especially in C. tropicalis. These findings indicate the need for region-specific antifungal treatment strategies to combat fungal infections effectively.

PEG-mediated synthesis, antibacterial, antifungal and antioxidant studies of some new 1,3,5-trisubstituted 2-pyrazolines

A new series of 1,3,5-trisubstituted 2-pyrazoline derivatives (3a-l) are synthesized in good to excellent yields from the corresponding chalcones (1a-h) and acid hydrazides (2a-e) in polyethylene glycol-400 (PEG-400) as a green reaction medium. The newly synthesized 2-pyrazoline derivatives are screened for their antibacterial and antifungal activity. The synthesized trisubstituted pyrazolines displayed moderate to good antibacterial and antifungal properties as compared with the standard reference penicillin and fluconazole drugs. Additionally, the antioxidant potential of the 1,3,5-trisubstituted 2-pyrazolines is evaluated by OH and DPPH assay. The 1,3,5-trisubstituted 2-pyrazolines showed good radical scavenger activity and were found as good antioxidant agents.

Antibacterial and antibiofilm activity of 1-thiocarbamoyl-3,5-diaryl-4,5-dihydro-1H pyrazoles and thiazoles in multidrug-resistant pathogens

To find novel antibiotic drugs, six 1-thiocarbamoyl-3,5-diaryl-4,5-dihydro-1H derivatives named 1b, 1d (pyrazoles), 2a, 2b, 2c, and 2d (thiazoles) were evaluated in silico and in vitro. The in silico analyses were based on ADME pharmacokinetic parameters (absorption, distribution, metabolism, and excretion). The in vitro antibacterial activity was evaluated in Gram-positive and Gram-negative species (Staphylococcus aureus ATCC® 25904, Staphylococcus epidermidis ATCC® 35984, Klebsiella pneumoniae ATCC® 700603, and Acinetobacter baumannii ATCC® 19606), by determination of minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC), kinetics curve, and antibiofilm assays. As results, the azoles have activity against the Gram-negative species K. pneumoniae ATCC® 700603 and A. baumannii ATCC® 19606. No antibacterial activity was observed for the Gram-positive bacteria evaluated. Thus, the azoles were evaluated against clinical isolates of K. pneumoniae carbapenemase (KPC) and A. baumannii multidrug-resistant (Ab-MDR). All azoles have antibacterial activity against Ab-MDR isolates (Gram-negative) with MIC values between 512 μg/mL and 1,024 μg/mL. Against KPC isolates the azoles 1b, 1d, and 2d present antibacterial activity (MIC = 1,024 μg/mL). In the kinetics curve assay, the 1b and 1d pyrazoles reduced significantly viable cells of Ab-MDR isolates and additionally inhibited 86.6 to 95.8% of the biofilm formation. The in silico results indicate high possibility to permeate the blood-brain barrier (2b) and was predict human gastrointestinal absorption (all evaluated azoles). Considering that the research and development of new antibiotics is a priority for drug-resistant pathogens, our study revealed the antibacterial and antibiofilm activity of novel azoles against K. pneumoniae and A. baumannii pathogens.

Chitosan-based sponges containing clotrimazole for the topical management of vulvovaginal candidiasis

Vulvovaginal candidiasis (VVC) persists as a worrying women's healthcare issue, often relying on suboptimal therapeutics. Novel intravaginal dosage forms focusing on improving patient acceptability and featuring improved biopharmaceutical properties could be interesting alternatives to available antifungal products. Different formulations of sponges based on chitosan (Ch), with or without crosslinking and co-formulated with poly(N-vinylcaprolactam) (PNVCL), were produced for the topical administration of clotrimazole (CTZ) and further tested for physicochemical properties, drug release, cytotoxicity and antifungal activity. Results showed that high amounts of CTZ (roughly 30-50 %) could be incorporated into sponges obtained by using a simple freeze-drying methodology. Cross-linking of Ch with ammonia affected the morphology and mechanical features of sponges and shifted the release profile from sustained (around 20 % and 60 % drug released after 4 h and 24 h, respectively) to fast-releasing (over 90 % at 4 h). The combination of PNVCL with non-crosslinked Ch also allowed tuning drug release, namely by increasing the initial amount of CTZ released in simulated vaginal fluid (roughly 40 % after 4 h), as compared to sponges featuring only non-crosslinked Ch. All formulations displayed low toxicity to cell lines derived from the female genital tract, with viability values kept above 70 % after 24 h incubation with sponge extracts. These also allowed maintaining the rapid onset of the antifungal effects of CTZ at minimum inhibitory concentrations ranging from 0.5 to 16 μg/mL for a panel of six different Candida spp. strains. Overall, proposed sponge formulations appear to be promising alternatives for the safe and effective management of VVC.

Molecular and Clinical Features of Fluconazole Non-susceptible Candida albicans Bloodstream Isolates Recovered in Korean Multicenter Surveillance Studies

Acquired fluconazole resistance (FR) in bloodstream infection (BSI) isolates of Candida albicans is rare. We investigated the FR mechanisms and clinical features of 14 fluconazole non-susceptible (FNS; FR and fluconazole-susceptible dose-dependent) BSI isolates of C. albicans recovered from Korean multicenter surveillance studies during 2006-2021. Mutations causing amino acid substitutions (AASs) in the drug-target gene ERG11 and the FR-associated transcription factor genes TAC1, MRR1, and UPC2 of the 14 FNS isolates were compared with those of 12 fluconazole-susceptible isolates. Of the 14 FNS isolates, eight and seven had Erg11p (K143R, F145L, or G464S) and Tac1p (T225A, R673L, A736T, or A736V) AASs, respectively, which were previously described in FR isolates. Novel Erg11p, Tac1p, and Mrr1p AASs were observed in two, four, and one FNS isolates, respectively. Combined Erg11p and Tac1p AASs were observed in seven FNS isolates. None of the FR-associated Upc2p AASs were detected. Of the 14 patients, only one had previous azole exposure, and the 30-day mortality rate was 57.1% (8/14). Our data show that Erg11p and Tac1p AASs are likely to contribute to FR in C. albicans BSI isolates in Korea and that most FNS C. albicans BSIs develop without azole exposure.

The pipeline for drugs for control and elimination of neglected tropical diseases: 2. Oral anti-infective drugs and drug combinations for off-label use

In its 'Road map for neglected tropical diseases 2021-2030', the World Health Organization outlined its targets for control and elimination of neglected tropical diseases (NTDs) and research needed to achieve them. For many NTDs, this includes research for new treatment options for case management and/or preventive chemotherapy. Our review of small-molecule anti-infective drugs recently approved by a stringent regulatory authority (SRA) or in at least Phase 2 clinical development for regulatory approval showed that this pipeline cannot deliver all new treatments needed. WHO guidelines and country policies show that drugs may be recommended for control and elimination for NTDs for which they are not SRA approved (i.e. for 'off-label' use) if efficacy and safety data for the relevant NTD are considered sufficient by WHO and country authorities. Here, we are providing an overview of clinical research in the past 10 years evaluating the anti-infective efficacy of oral small-molecule drugs for NTD(s) for which they are neither SRA approved, nor included in current WHO strategies nor, considering the research sponsors, likely to be registered with a SRA for that NTD, if found to be effective and safe. No such research has been done for yaws, guinea worm, Trypanosoma brucei gambiense human African trypanosomiasis (HAT), rabies, trachoma, visceral leishmaniasis, mycetoma, T. b. rhodesiense HAT, echinococcosis, taeniasis/cysticercosis or scabies. Oral drugs evaluated include sparfloxacin and acedapsone for leprosy; rifampicin, rifapentin and moxifloxacin for onchocerciasis; imatinib and levamisole for loiasis; itraconazole, fluconazole, ketoconazole, posaconazole, ravuconazole and disulfiram for Chagas disease, doxycycline and rifampicin for lymphatic filariasis; arterolane, piperaquine, artesunate, artemether, lumefantrine and mefloquine for schistosomiasis; ivermectin, tribendimidine, pyrantel, oxantel and nitazoxanide for soil-transmitted helminths including strongyloidiasis; chloroquine, ivermectin, balapiravir, ribavirin, celgosivir, UV-4B, ivermectin and doxycycline for dengue; streptomycin, amoxicillin, clavulanate for Buruli ulcer; fluconazole and isavuconazonium for mycoses; clarithromycin and dapsone for cutaneous leishmaniasis; and tribendimidine, albendazole, mebendazole and nitazoxanide for foodborne trematodiasis. Additional paths to identification of new treatment options are needed. One promising path is exploitation of the worldwide experience with 'off-label' treatment of diseases with insufficient treatment options as pursued by the 'CURE ID' initiative.

[Anti-infective treatment of fungal infections by Candida and Aspergillus]

BACKGROUND

Invasive fungal infections caused by Candida or Aspergillus are associated with a high mortality. Knowledge about the risk factors, diagnosis and treatment management is crucial for improving the survival of those affected.

OBJECTIVE

To give a practical overview about risk factors and treatment management of Candida and Aspergillus infections as well as providing an outlook on new antifungal agents.

MATERIAL AND METHODS

Summary of the relevant literature and recommendations on candidemia and invasive candidiasis as well as invasive and chronic pulmonary aspergillosis.

RESULTS

The first line treatment of candidemia and invasive candidiasis are echinocandins including caspofungin, anidulafungin and micafungin. Regular blood cultures have to be taken to determine the duration of treatment. After the first negative control blood culture treatment should be continued for another 14 days. The first line treatment of invasive pulmonary aspergillosis is azoles including voriconazole and isavuconazole. The duration of treatment depends on disease severity and is recommended for 6-12 weeks. The duration of treatment for chronic pulmonary aspergillosis is 6-12 months. Therapeutic drug monitoring is recommended for voriconazole and for posaconazole. New antifungal agents including olorofim, fosmanogepix, opelconazole, rezafungin or ibrexafungerp will broaden the therapeutic spectrum in the foreseeable future.

CONCLUSION

Knowledge about risk factors and the correct treatment management is crucial for the survival of patients with invasive fungal infections.

Potential role of broad-spectrum azoles as therapy for Malasezzia bloodstream infection

Amphotericin B is the currently recommended therapy for Malassezia invasive infection (MII), but this drug requires intravenous administration and is associated with significant toxicity. The role of broad-spectrum azoles in managing MII is not clear. We describe two cases of MII due to M. pachydermatis and M. furfur that were successfully treated with posaconazole and reviewed the literature to assess the position of posaconazole in treating MII.

Nanotechnology-Based Drug Delivery of Topical Antifungal Agents

Among the various prominent fungal infections, superficial ones are widespread. A large number of antifungal agents and their formulations for topical use are commercially available. They have some pharmacokinetic limitations which cannot be retracted by conventional delivery systems. While nanoformulations composed of lipidic and polymeric nanoparticles have the potential to overcome the limitations of conventional systems. The broad spectrum category of antifungals i.e. azoles (ketoconazole, voriconazole, econazole, miconazole, etc.) nanoparticles have been designed, prepared and their pharmacokinetic and pharmacodynamic profile was established. This review briefly elaborates on the types of nano-based topical drug delivery systems and portrays their advantages for researchers in the related field to benefit the available antifungal therapeutics.

Instillation of Amphotericin B by bronchoscopy combined with systemic voriconazole in advanced non-small cell lung cancer patients with chronic cavitary pulmonary aspergillosis: A case series and literature review

Although the treatment of aspergillosis has been studied for years, the optimal nonsurgical treatment of chronic cavitary pulmonary aspergillosis (CCPA) remains unsatisfactory, especially in lung cancer. We report two advanced non-small cell lung cancer (NSCLC) patients who recovered from CCPA following instillation of Amphotericin B (AmB) by bronchoscopy combined with systemic voriconazole. The first patient was diagnosed with lung adenocarcinoma after right upper lobe resection and was treated with anaplastic lymphoma kinase-targeted therapy. Chest computed tomography (CT) revealed a right pulmonary cavity containing solid materials. The second patient was diagnosed with squamous cell carcinoma and received immunotherapy following surgery, chemotherapy, and radiotherapy. Chest CT tomography revealed a mass in the right lung cavity. Both patients' cultures and next-generation sequencing of their bronchoalveolar lavage (BAL) samples revealed presence of Aspergillus fumigatus. In addition, the galactomannan test of both patients BAL samples was positive. Systemic voriconazole was prescribed based on in vitro susceptibility testing. The chest images and clinical symptoms of both patients did not improve after one month of voriconazole therapy within the therapeutic blood concentration. Considering the low local concentrations of antifungals against CCPA, AmB instillation by bronchoscopy combined with systemic voriconazole was utilized. The chest CT images and clinical symptoms of both patients markedly improved in the following third month. Instillation of AmB combined with systemic voriconazole may be a promising treatment option for NSCLC patients with CCPA who fail voriconazole monotherapy.

An overview of opportunistic fungal infections associated with COVID-19

The COVID-19 survivors and long-term steroid administered patients exhibit a variety of fungal co-infections. The lives of COVID-19 patients and survivors are hampered by fungal species of the genera Candida, Aspergillus, and Mucor. There have been cases of mucormycosis, aspergillosis, and candidiasis in COVID-19 patients. The treatments given to these opportunistic fungal infections include polyene like amphotericin B, azoles including imidazoles like ketoconazole, miconazole, and triazoles like fluconazole, voriconazole, itraconazole, Echinocandin derivatives like- caspofungin, micafungin, immunomodulatory therapy, granulocyte transfusion, etc. A successful recovery and the reduction of fatalities depend on prompt diagnosis and treatment. To reduce mortality, advanced techniques to identify such uncommon infections at a very early stage are necessary. This review's goal is to provide a summary of the systemic and superficial opportunistic fungal infections that the COVID-19 survivors were dealing with, including information on illness incidence, pathogenicity, and treatment.

Combination therapy in Mucormycosis: Current evidence from the world literature, a mini review

The emergence of Mucorales infections is an urgent global public health threat rapidly disseminating during the current COVID-19 pandemic. Invasive mucormycosis carries significant morbidity and mortality; this is further compounded by the lack of newer effective antifungals on the horizon. Liposomal Amphotericin (L-AMB) is currently considered the cornerstone of antifungals therapy against mucormycosis; However, two decades later (since the introduction of L-AMB), the outcome remains dismal. Furthermore, adverse events related to therapeutic doses of L-AMB are also a hindrance. There is an imperative need for an alternative therapeutic approach to reduce the high mortality. One such approach is to combine the amphotericin with other agents (e.g., caspofungin, posaconazole, isavuconazole, and iron chelators) that can work synergistically or help in reducing the therapeutic doses of L-AMB. This review aims to highlight the various treatment approaches by gathering the clinical evidence from the literature and considering all potential pharmacological combinations that can provide the direction for future studies.

Can amphotericin B and itraconazole be co-delivered orally? Tailoring oral fixed-dose combination coated granules for systemic mycoses

The incidence and prevalence of invasive fungal infections have increased significantly over the last few years, leading to a global health problem due to the lack of effective treatments. Amphotericin B (AmB) and itraconazole (ITR) are two antifungal drugs with different mechanisms of action. In this work, AmB and ITR have been formulated within granules to elicit an enhanced pharmacological effect, while enhancing the oral bioavailability of AmB. A Quality by Design (QbD) approach was utilised to prepare fixed-dose combination (FDC) granules consisting of a core containing AmB with functional excipients, such as inulin, microcrystalline cellulose (MCC), chitosan, sodium deoxycholate (NaDC) and Soluplus® and polyvinyl pyrrolidone (PVP), coated with a polymeric layer containing ITR with Soluplus® or a combination of Poloxamer 188 and hydroxypropyl methyl cellulose-acetyl succinate (HPMCAS). A Taguchi design of experiments (DoE) with 7 factors and 2 levels was carried out to understand the key factors impacting on the physicochemical properties of the formulation followed by a Box-Behnken design with 3 factors in 3 levels chosen to optimise the formulation parameters. The core of the FDC granules was obtained by wet granulation and later coated using a fluidized bed. In vitro antifungal efficacy was demonstrated by measuring the inhibition halo against different species of Candida spp., including C. albicans (24.19-30.48 mm), C. parapsilosis (26.38-27.84 mm) and C. krusei (11.48-17.92 mm). AmB release was prolonged from 3 to 24 h when the AmB granules were coated. In vivo in CD-1 male mice studies showed that these granules were more selective towards liver, spleen and lung compared to kidney (up to 5-fold more selective in liver, with an accumulation of 8.07 µg AmB/g liver after twice-daily 5 days administration of granules coated with soluplus-ITR), resulting in an excellent oral administration option in the treatment of invasive mycosis. Nevertheless, some biochemical alterations were found, including a decrease in blood urea nitrogen (∼17 g/dl) and alanine aminotransferase (<30 U/l) and an increase in the levels of bilirubin (∼0.2 mg/dl) and alkaline phosphatase (<80 U/l), which could be indicative of a liver failure. Once-daily regimen for 10 days can be a promising therapy.

Mucormycosis: A hidden mystery of fungal infection, possible diagnosis, treatment and development of new therapeutic agents

Mucormycosis is a fungal infection which got worsens with time if not diagnosed and treated. The current COVID-19 pandemic has association with fungal infection specifically with mucormycosis. Already immunocompromised patients are easy target for COVID-19 and mucormycosis as well. COVID-19 infection imparts in weak immune system so chances of infection is comparatively high in COVID-19 patients. Furthermore, diabetes, corticosteroid medicines, and a weakened immune system are the most prevalent risk factors for this infection as we discussed in case studies here. The steroid therapy for COVID-19 patients sometimes have negative impact on the patient health and this state encounters many infections including mucormycosis. There are treatments available but less promising and less effective. So, researchers are focusing on the promising agents against mucormycosis. It is reported that early treatment with liposomal amphotericin B (AmB), manogepix, echinocandins isavuconazole, posacanazole and other promising therapeutic agents have overcome the burden of mucormycosis. Lipid formulations of AmB have become the standard treatment for mucormycosis due to their greater safety and efficacy. In this review article, we have discussed case studies with the infection of mucormycosis in COVID-19 patients. Furthermore, we focused on anti-mucormycosis agents with mechanism of action of various therapeutics, including coverage of new antifungal agents being investigated as part of the urgent global response to control and combat this lethal infection, especially those with established risk factors.

Hepatotoxicity Induced by Azole Antifungal Agents: A Review Study

Context

Fungal infections are very common, and several medications are used to treat them. Azoles are prescribed widely to treat fungal infections. In addition to therapeutic effects, any drug can be accompanied by side effects in patients. One of the most important complications in this regard is liver injury. Therefore, hepatotoxicity induced by azole antifungal drugs were reviewed in this study.

Evidence Acquisition

English scientific papers were evaluated to review the effects of hepatotoxicity by azole antifungal agents, and the related studies' results were summarized using a table. The systematic search was implemented on electronic databases, including PubMed, Google Scholar, and Science Direct. Original articles and review articles that were published before April 1, 2022, were included in the study. Those articles without available full text or non-English articles were excluded. Also, articles that reported pediatric data were excluded.

Results

Most studies have reported the effects of hepatotoxicity by azole antifungal agents, and their mechanisms have been described.

Conclusions

Clinical evaluations regarding the hepatotoxicity of antifungal agents provided in the literature were reviewed. Therefore, it is recommended to prescribe these drugs with caution in high-risk patients suffering from liver diseases, and patients should be monitored for hepatotoxicity. However, more research is needed to evaluate the hepatotoxicity of azole antifungal agents and select appropriate drugs according to cost-effectiveness and the side effects' profiles, relying on lower incidence of this liver complication.

The RNA Helicase Ski2 in the Fungal Pathogen Cryptococcus neoformans Highlights Key Roles in Azoles Resistance and Stress Tolerance

The yeast SKI (superkiller) complex was originally identified from cells that were infected by the M 'killer' virus. Ski2, as the core of the SKI complex, is a cytoplasmic cofactor and regulator of RNA-degrading exosome. The putative RNA helicase Ski2 was highly conserved from yeast to animals and has been demonstrated to play a key role in the regulation of RNA surveillance, temperature sensitivity, and growth in several yeasts but not yet in Cryptococcus neoformans (C. neoformans). Here, we report the identification of a gene encoding an equivalent Ski2 protein, named SKI2, in the fungal pathogen C. neoformans. To obtain insights into the function of Ski2, we created a mutant strain, ski2Δ, with the CRISPR-Cas9 editing tool. Disruption of SKI2 impaired cell wall integrity. Further investigations revealed the defects of the ski2Δ mutant in resistance to osmotic stresses and extreme growth temperatures. However, significantly, the ability to undergo invasive growth under nutrient-depleted conditions was increased in the ski2Δ mutant. More importantly, our results showed that the ski2Δ mutant exhibited slightly lower virulence and severe susceptibility to anti-ribosomal drugs by comparison to the wild type, but it developed multidrug resistance to azoles and flucytosine. By constructing the double deletion strain ski2Δafr1Δ, we verified that increased Afr1 in ski2Δ contributed to the azole resistance, which might be influenced by nonclassical small interfering RNA. Our work suggests that Ski2 plays critical roles in drug resistance and regulation of gene transcription in the yeast pathogen C. neoformans.

Synthesis, biological evaluation and molecular modeling studies of novel 1,2,3-triazole-linked menadione-furan derivatives as P2X7 inhibitors

The P2X7 receptor (P2X7R) is an ion channel that promotes the passage of ions through the membrane through brief stimulation once activated by ATP, its endogenous opener. However, prolonged stimulation with ATP, which occurs in pathological processes, opens a nonselective pore in the plasma membrane, allowing the passage of large molecules and leading to cytokine release or even cell death. In this sense, the search for new inhibitors for this receptor has attracted a great deal of attention in recent years. Considering the booming of biomass upgrading reactions in recent years and the continued efforts to synthesize biologically active molecules containing the 1,2,3-triazole ring, in the present work, we aimed to investigate whether triazole-linked menadione-furan derivatives could present P2X7R inhibitory activity. The novel compounds were tested for their inhibitory activity on ATP-induced dye uptake in peritoneal macrophages. Some have shown promising results, having displayed IC₅₀ values lower than that of the P2X7R inhibitor BBG. Molecular docking studies also indicated that the active compounds bind to an allosteric site on P2X7R, presenting potential P2X7R inhibition.

Candida Empyema in Febrile Neutropenia - Augmented value of direct inoculation into BacT/Alert blood culture vials

Candida empyema is an uncommon complication of febrile neutropenia. We present 4 such cases which highlight the importance of direct inoculation of body fluids in automated blood culture bottle leading to increased yield. Our cases and review of literature also highlight that echinocandins have poor penetration into pleural fluid; azoles (especially voriconazole) should be preferred as drug of choice.

Arylated analogues of cypronazole: fungicidal effect and activity on human fibroblasts. Docking analysis and molecular dynamics simulations

Triadimefon (TDM) and cyproconazole (CPZ) are two triazoles widely used as fungicides. Several azoles were synthesised starting from commercial TDM and CPZ. The compounds were evaluated against phytopathogenic filamentous fungi, including Aspergillus fumigatus (AF), A. niger (AN), A. ustus (AU), A. japonicus (AJ), A. terreus (AT), Fusarium oxysporum and Botrytis cinerea isolated from grapevine in the province of San Juan, Argentina. Three of the synthesised compounds (1-(Biphenyl-4-yloxy)-3,3-dimethyl-1-(1H-1,2,4-triazol-1-yl)butan-2-one, 1; 2-(Biphenyl-4-yl)-3-cyclopropyl-1-(1H-1,2,4-triazol-1-yl)butan-2-ol, 3; 3-Cyclopropyl-2-(4'-fluorobiphenyl-4-yl)-1-(1H-1,2,4-triazol1-yl)butan-2-ol, 4) presented remarkable in vitro fungicidal properties, with better effects than TDM and CPZ on some of the target fungi. Cytotoxicity was assessed using human lung fibroblasts MRC5. Derivative 1, with IC₅₀ values of 389.4 µM, was less toxic towards MRC-5 human lung fibroblasts than commercial TDM (248.5 µM) and CPZ (267.4 µM). Docking analysis and molecular dynamics simulations suggest that the compounds present the same interaction in the binding pocket of the CYP51B enzyme and with the same amino acids as CPZ. The derivatives investigated could be considered broad-spectrum but with some selectivity towards imperfect fungi.

Exploration of structural requirements for azole chemicals towards human aromatase CYP19A1 activity: Classification modeling, structure-activity relationships and read-across study

Human aromatase, also called CYP19A1, plays a major role in the conversion of androgens into estrogens. Inhibition of aromatase is an important target for estrogen receptor (ER)-responsive breast cancer therapy. Use of azole compounds as aromatase inhibitors is widespread despite their low selectivity. A toxicological evaluation of commonly used azole-based drugs and agrochemicals with respect to CYP19A1is currently requested by the European Union- Registration, Evaluation, Authorization and Restriction of Chemicals (EU-REACH) regulations due to their potential as endocrine disruptors. In this connection, identification of structural alerts (SAs) is an effective strategy for the toxicological assessment and safe drug design. The present study describes the identification of SAs of azole-based chemicals as guiding experts to predict the aromatase activity. Total 21 SAs associated with aromatase activity were extracted from dataset of 326 azole-based drugs/chemicals obtained from Tox21 library. A cross-validated classification model having high accuracy (error rate 5%) was proposed which can precisely classify azole chemicals into active/inactive toward aromatase. In addition, mechanistic details and toxicological properties (agonism/antagonism) of azoles with respect to aromatase were explored by comparing active and inactive chemicals using structure-activity relationships (SAR). Lastly, few structural alerts were applied to form chemical categories for read-across applications.

Synthesis and in vitro and in silico studies of 1H- and 2H-1,2,3-triazoles as antichagasic agents

1,2,3-triazole heterocycles stand out in medicinal chemistry for having great structural diversity and bioactivities. In this study, two series of triazoles were synthesized. One was obtained by the 1,3-dipolar cycloaddition reaction between ethyl cyanoacetate and several phenyl azides forming 1H-1,2,3-triazoles and the other by rearrangement of Dimroth forming and 2H-1,2,3-triazoles. Both series were shown to be active against the epimastigote form of Trypanosoma cruzi. The 1,2,3-triazoles 16d (S.I. between 100 and 200), 17d and 16f (S.I. > 200) were the most active compounds and capable of breaking the plasma membrane of trypomastigotes acting on CYP51 and inhibiting ergosterol synthesis. Candidate 16d exhibited the best and most favorable profile when interacting with CYP51.

Evaluation of N-aryl-β-alanine derivatives as anticancer agents in triple-negative breast cancer and glioblastoma in vitro models

Synthesis of β-amino acid derivatives containing hydrazone and azole moieties is described. For this purpose, the appropriate hydrazide was treated with aromatic aldehydes, ketones and phenyl iso(thio)cyanates to obtain the desired outcome. The synthesized target compounds were evaluated for their anticancer properties. The assay displayed 3,3'-((2,6-diethylphenyl)azanediyl)bis(N'-(benzylidene)propanehydrazide) to possess the convincing anticancer effect against triple-negative breast cancer cells in vitro. To further study the anticancer properties of compounds containing a hydrazone moiety in breast cancer, series of previously and newly prepared dihydrazones were investigated. It was determined that derivatives with the bis(N'-(4-bromobenzylidene) fragment in the structure are exclusively cytotoxic to cancer cells. The most active compounds against both cell lines were those containing electron withdrawing 4-BrPh or 4-ClPh moieties, together with either chlorine, bromine or iodine groups in para position of phenyl ring. Selected two representative compounds showed migrastatic activity in MDA-MB-231 cell line, where both of them reduced the growth of breast cancer and glioblastoma cell 3D cultures and inhibited cell colony formation. 2009 Elsevier Ltd. All rights reserved.

Human-relevant concentrations of the antifungal drug clotrimazole disrupt maternal and fetal steroid hormone profiles in rats

Clotrimazole is a non-prescription and broad-spectrum antifungal drug sold under brand names such as Canesten® and Lotrimin®. It is used to treat different types of fungal infections, from oral thrush to athlete's foot and vaginal mycosis. The level of exposure to clotrimazole is uncertain, as the exact usage amongst self-medicating patients is unclear. Recent studies have raised potential concern about the unsupervised use of clotrimazole during pregnancy, especially since it is a potent inhibitor of CYP enzymes of the steroidogenesis pathway. To address some of these concerns, we have assessed the effects of intrauterine exposure to clotrimazole on developing rat fetuses. By exposing pregnant rats to clotrimazole 25 or 75 mg/kg bw/day during gestation days 7-21, we obtained internal fetal concentrations close to those observed in humans. These in vivo data are in strong agreement with our physiologically-based pharmacokinetic (PBK)-modelled levels. At these doses, we observed no obvious morphological changes to the reproductive system, nor shorter male anogenital distance; a well-established morphometric marker for anti-androgenic effects in male offspring. However, steroid hormone profiles were significantly affected in both maternal and fetal plasma, in particular pronounced suppression of estrogens was seen. In fetal testes, marked up-concentration of hydroxyprogesterone was observed, which indicates a specific action on steroidogenesis. Since systemic clotrimazole is rapidly metabolized in humans, relevant exposure levels may not in itself cause adverse changes to the reproductive systems. Its capacity to significantly alter steroid hormone concentrations, however, suggests that clotrimazole should be used with caution during pregnancy.

[Mucormycosis: Current and future management perspective]

Infections caused by mucorales, with an increasing incidence after candidiasis and aspergillosis, are characterized by the fast angioinvasion of blood vessels and invasion of neighboring organs or structures. Mucorales most commonly cause rhinocerebral, pulmonary, cutaneous, digestive or disseminated infections, and their spread is favored by certain underlying diseases (diabetes, kidney failure) and risk factors (neutropenia, immunosuppression, iron overload). These infections have a high mortality rate, over 40% in many series, and the key to their cure depends on both an early diagnosis and an antifungal treatment, associated in most cases with extensive surgical debridement and other adjunctive therapies. Currently, there are international guidelines, not only local ones, for the management of mucormycosis, in which it is considered by consensus and with a strong recommendation that first-line treatment with high-dose liposomal amphotericin B is the best choice. The combined antifungal treatment of polyene agents with triazoles or candins remains in open debate.

Antifungals in Clinical Use and the Pipeline

Over the past 15 years, there has been an increase in the development and utilization of newer antifungal agents. The ideal antifungal, however, in regard to spectrum of activity, pharmacokinetic/pharmacodynamic properties, development of resistance, safety, and drug interaction profile remains elusive. This article reviews pharmacologic aspects of Food and Drug Administration-approved polyenes, flucytosine, azoles, and echinocandins as well as promising pipeline antifungal agents. Unique properties of these newer agents are highlighted. The clinical role of established and investigational antifungal agents as treatment and/or prevention of invasive fungal infections is discussed.

Transcriptomic studies on Purpureocillium lilacinum reveal molecular mechanisms of response to fluconazole and itraconazole

Filamentous fungus Purpureocillium lilacinum is an emerging pathogen that infects immunocompromised and immunocompetent individuals and is resistant to several azole molecules. Although azole resistance mechanisms are well studied in Aspergillus sp. and Candida sp., there are no studies to date reporting P. lilacinum molecular response to these molecules. The aim of this study was to describe P. lilacinum molecular mechanisms involved in antifungal response against fluconazole and itraconazole. Transcriptomic analyses showed that gene expression modulation takes place when P. lilacinum is challenged for 12 h with fluconazole (64 μg/mL) or itraconazole (16 μg/mL). The antifungals acted on the ergosterol biosynthesis pathway, and two homologous genes coding for cytochrome P450 51 enzymes were upregulated. Genes coding for efflux pumps, such as the major facilitator superfamily transporter, also displayed increased expression in the treated samples. We propose that P. lilacinum develops antifungal responses by raising the expression levels of cytochrome P450 enzymes and efflux pumps. Such modulation could confer P. lilacinum high levels of target enzymes and could lead to the constant withdrawal of antifungals, which would force an increase in the administration of antifungal medications to achieve fungal morbidity or mortality. The findings in this work could aid in the decision-making for treatment strategies in cases of P. lilacinum infection.

Biological Evaluation of Selected 1,2,3-triazole Derivatives as Antibacterial and Antibiofilm Agents

BACKGROUND

Resistance to antimicrobial agents is a major public health problem, being Staphylococcus aureus prevalent in infections in hospital and community environments and, admittedly, related to biofilm formation in biotic and abiotic surfaces. Biofilms form a complex and structured community of microorganisms surrounded by an extracellular matrix adhering to each other and to a surface that gives them even more protection from and resistance against the action of antimicrobial agents, as well as against host defenses.

METHODS

Aiming to control and solve these problems, our study sought to evaluate the action of 1,2,3- triazoles against a Staphylococcus aureus isolate in planktonic and in the biofilm form, evaluating the activity of this triazole through Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) tests. We have also performed cytotoxic evaluation and Scanning Electron Microscopy (SEM) of the biofilms under the treatment of the compound. The 1,2,3-triazole DAN 49 showed bacteriostatic and bactericidal activity (MIC and MBC 128 μg/mL). In addition, its presence interfered with the biofilm formation stage (1/2 MIC, p <0.000001) and demonstrated an effect on young preformed biofilm (2 MICs, p <0.05).

RESULTS

Scanning Electron Microscopy images showed a reduction in the cell population and the appearance of deformations on the surface of some bacteria in the biofilm under treatment with the compound.

CONCLUSION

Therefore, it was possible to conclude the promising anti-biofilm potential of 1,2,3-triazole, demonstrating the importance of the synthesis of new compounds with biological activity.

Nanoparticles as a Tool for Broadening Antifungal Activities

Fungal infections are diseases that are considered neglected although their infection rates have increased worldwide in the last decades. Thus, since the antifungal arsenal is restricted and many strains have shown resistance, new therapeutic alternatives are necessary. Nanoparticles are considered important alternatives to promote drug delivery. In this sense, the objective of the present study was to evaluate the contributions of newly developed nanoparticles to the treatment of fungal infections. Studies have shown that nanoparticles generally improve the biopharmaceutical and pharmacokinetic characteristics of antifungals, which is reflected in a greater pharmacodynamic potential and lower toxicity, as well as the possibility of prolonged action. It also offers the proposition of new routes of administration. Nanotechnology is known to contribute to a new drug delivery system, not only for the control of infectious diseases but for various other diseases as well. In recent years, several studies have emphasized its application in infectious diseases, presenting better alternatives for the treatment of fungal infections.

Organic Antifungal Drugs and Targets of Their Action

In recent decades, there has been a significant increase in the number of fungal diseases. This is due to a wide spectrum of action, immunosuppressants and other group drugs. In terms of frequency, rapid spread and globality, fungal infections are approaching acute respiratory infections. Antimycotics are medicinal substances endorsed with fungicidal or fungistatic properties. For the treatment of fungal diseases, several groups of compounds are used that differ in their origin (natural or synthetic), molecular targets and mechanism of action, antifungal effect (fungicidal or fungistatic), indications for use (local or systemic infections), and methods of administration (parenteral, oral, outdoor). Several efforts have been made by various medicinal chemists around the world for the development of antifungal drugs with high efficacy with the least toxicity and maximum selectivity in the area of antifungal chemotherapy. The pharmacokinetic properties of the new antimycotics are also important: the ability to penetrate biological barriers, be absorbed and distributed in tissues and organs, get accumulated in tissues affected by micromycetes, undergo drug metabolism in the intestinal microflora and human organs, and in the kinetics of excretion from the body. There are several ways to search for new effective antimycotics: - Obtaining new derivatives of the already used classes of antimycotics with improved activity properties. - Screening of new chemical classes of synthetic antimycotic compounds. - Screening of natural compounds. - Identification of new unique molecular targets in the fungal cell. - Development of new compositions and dosage forms with effective delivery vehicles. The methods of informatics, bioinformatics, genomics and proteomics were extensively investigated for the development of new antimycotics. These techniques were employed in finding and identification of new molecular proteins in a fungal cell; in the determination of the selectivity of drugprotein interactions, evaluation of drug-drug interactions and synergism of drugs; determination of the structure-activity relationship (SAR) studies; determination of the molecular design of the most active, selective and safer drugs for the humans, animals and plants. In medical applications, the methods of information analysis and pharmacogenomics allow taking into account the individual phenotype of the patient, the level of expression of the targets of antifungal drugs when choosing antifungal agents and their dosage. This review article incorporates some of the most significant studies covering the basic structures and approaches for the synthesis of antifungal drugs and the directions for their further development.

Isatin-derived azoles as new potential antimicrobial agents: Design, synthesis and biological evaluation

Novel antibiotics are forced to be developed on account of multidrug-resistant bacteria with serious threats to human health. This work developed isatin-derived azoles as new potential antimicrobial agents. Bioactive assay revealed that isatin hybridized 1,2,4-triazole 7a exhibited excellent inhibitory activity against E. coli ATCC 25,922 with an MIC value of 1 µg/mL, which was 8-fold more potent than reference drug norfloxacin. The active molecule 7a possessed the ability to kill some bacteria and fungi as well as displayed low propensity to induce resistance towards E. coli ATCC25922. Preliminary mechanism investigation indicated that hybrid 7a might block deoxyribonucleic acid (DNA) replication by intercalating with DNA and possibly interacting with DNA polymerase III, thus exerting its antimicrobial potency.

Transcriptome analysis of fetal rat testis following intrauterine exposure to the azole fungicides triticonazole and flusilazole reveals subtle changes despite adverse endocrine effects

Azoles are used in agriculture and medicine to combat fungal infections. We have previously examined the endocrine disrupting properties of the agricultural azole fungicides triticonazole and flusilazole. Triticonazole displayed strong androgen receptor (AR) antagonism in vitro, whereas in utero exposure resulted in anti-androgenic effects in vivo evidenced by shorter anogenital distance (AGD) in fetal male rats. Flusilazole displayed strong AR antagonism, but less potent than triticonazole, and disrupted steroidogenesis in vitro, whereas in utero exposure disrupted fetal male plasma hormone levels. To elaborate on how these azole fungicides can disrupt male reproductive development by different mechanisms, and to investigate whether feminization effects such as short AGD in males can also be detected at the transcript level in fetal testes, we profiled fetal testis transcriptomes after in utero exposure to triticonazole and flusilazole by 3'Digital Gene Expression (3'DGE). The analysis revealed few transcriptional changes after exposure to either compound at gestation day 17 and 21. This suggests that the observed influence of flusilazole on hormone production may be by directly targeting steroidogenic enzyme activity in the testis at the protein level, whereas observations of shorter AGD by triticonazole may primarily be due to disturbed androgen signaling in androgen-sensitive tissues. Expression of Calb2 and Gsta2 was altered by flusilazole but not triticonazole and may pinpoint novel pathways of disrupted testicular steroid synthesis. Our findings have wider implication for how we integrate omics data in chemical testing frameworks, including selection of non-animal test methods and building of Adverse Outcome Pathways for regulatory purposes.

Anammox enrichment culture has unexpected capabilities to biotransform azole contaminants of emerging concern

Azoles are contaminants of emerging concern. They have a ubiquitous presence in the environment due to their wide variety of uses. This study investigated the fate of two commonly occurring azole compounds in an anammox enrichment culture. The results showed that 1H-pyrazole (PA) and 1H-1,2,4-triazole (TA) were biotransformed yielding major biotransformation products, 3-amino-1H-pyrazole and 3-amino-1H-1,2,4-triazole, respectively. Nitrate and glucose greatly stimulated the biotransformation. Under optimized conditions, 80.7% of PA and 16.4% of TA were biotransformed in an incubation period of 6 days. High molar product yield of 84.5% and 83.6% was observed per mole of PA and TA biotransformed, respectively. This novel and selective biotransformation constitutes the first report on the microbial biotransformation of PA and is amongst the very few reports on the biotransformation of TA. This study also provides evidence that anammox enrichments have unexpected capabilities to biotransform organic contaminants of emerging concern.

Reversal of azole resistance in Candida albicans by oridonin

OBJECTIVES

Candida albicans is a yeast that causes fungal infections with high mortality and is typically resistant to azole drugs. To overcome this resistance, we explored the combined use of oridonin (ORI) and three azole drugs, namely fluconazole (FLC), itraconazole (ITR) and voriconazole (VOR). Azole-resistant C. albicans strains were obtained from cancer patients and the reversal of drug resistance in these strains was investigated.

METHODS

The synergistic antifungal activity of ORI and azole drugs was measured by checkerboard microdilution and time-kill assays. The resistance reversal mechanisms, namely inhibition of drug efflux and induction of apoptosis, were investigated by flow cytometry. Expression levels of the efflux pump-related genesCDR1 and CDR2 were assessed by RT-qPCR.

RESULTS

The efflux pump inhibition assay with ORI showed that the minimum inhibitory concentrations (MICs) of FLC (128-fold), ITR (64-fold) and VOR (250-fold) decreased significantly. Upregulation of genes encodingCDR1 and CDR2 was confirmed in the resistant strain. The sensitising effect of ORI on FLC in the treatment of C. albicans also included the promotion of apoptosis.

CONCLUSION

We demonstrated that combining azoles with ORI exerted potent synergism and that ORI could promote sensitisation to azoles in azole-resistantC. albicans. The discovery that ORI can effectively inhibit drug efflux and promote apoptosis may provide new insights and therapeutic strategies to overcome increasing azole resistance in C. albicans.

Azole pharmaceuticals induce germinal vesicle breakdown (GVBD) in preovulatory oocytes of zebrafish (Danio rerio): an in vitro study

Azoles, the antifungal pharmaceuticals are emerging as a new class of water contaminants with a potential to influence the endocrine physiology of surrounding aquatic fauna. In this study, we made an attempt to assess the relative efficacy of widely used azoles belonging to two subclasses, i.e., (i) triazoles (letrozole, fluconazole, itraconazole) and (ii) imidazoles (ketaconazole, ornidazole, clotrimazole), on the onset of germinal vesicle breakdown (GVBD) (an initial step in the final maturation of oocytes) in fully grown preovulatory oocytes of zebrafish (Danio rerio) using an in vitro model. Oocytes (> 650 μm) isolated manually from gravid ovaries were exposed to (i) 0.01 and/or 0.1, 1.0, 5.0, 10, 15, and 20 ng/ml and (ii) 1.0, 2.0, 3.0, 4.0, and 5.0 μg/ml of drugs. Zebrafish Ringer's solution (vehicle) and 0.01% ethyl alcohol (solvent) were used as negative controls. 17α, 20 β-Dihydroxy-4-pregnen-3-one (17α-DHP) and diethylstibestrol (DES), potent inducers of GVBD in fish, were used as positive controls. GVBD was scored hourly from 0-6 h. In negative controls, there were no indications of GVBD even at the 6^th hour, while in 17α-DHP- and DES-exposed oocytes, GVBD was initiated from the 1^st hour, reaching 80% and 76% respectively at the 6^th hour. Among azoles, letrozole induced GVBD in 73-85%, fluconazole (30-33%), itraconazole (23-33%), ketaconazole (46-53%), ornidazole (36-40%), and clotrimazole (30-33%) of oocytes. These results suggest that azole pharmaceuticals induce GVBD in fish oocytes that may be attributed to their variable degree of cytochrome P450 enzyme inhibitor activity.

Impact of biofilm formation and azoles' susceptibility in Scedosporium/Lomentospora species using an in vitro model that mimics the cystic fibrosis patients' airway environment

BACKGROUND

Scedosporium species are the second most isolated filamentous fungi from cystic fibrosis (CF) patients; however, little is known about their virulence aspects in a CF environment. In this context, the current study aimed to evaluate the (i) antifungal susceptibility profiles, (ii) ability to form biofilm and (iii) impact of biofilm formation on the susceptibility to azoles in 21 clinical isolates of Scedosporium recovered from CF patients.

METHODS

Scedosporium apiospermum (n=6), S. aurantiacum (n=6), S. minutisporum (n=3) and Lomentospora prolificans (n=6) were firstly used to compare the antifungal susceptibility profile using a standard culture broth (RPMI-1640) and a mucin (M)-containing synthetic CF sputum medium (SCFM). The ability to form biofilms was investigated in polystyrene microtiter plates containing Sabouraud-dextrose (a classical medium), SCFM and SCFM+M. Mature biofilms were tested for their susceptibility to azoles by microdilution assay.

RESULTS

Our results showed that the minimum inhibitory concentrations (MICs) for planktonic conidia ranged from 0.25 to >16.0 mg/L for voriconazole and 1.0 to >16.0 mg/L for posaconazole. Overall, the MICs for azoles increased from 2- to 8-folds when the susceptibility tests were performed using SCFM+M compared to RPMI-1640. All fungi formed robust biofilms on polystyrene surface at 72 h, with a significant increase in the MICs (ranging from 128- to 1024-times) against both azoles compared to the planktonic cells.

CONCLUSION

These findings confirm the challenge of antifungal treatment of CF patients infected with Scedosporium/Lomentospora and also demonstrated a strong biofilm formation, with extensive increase in antifungal resistance, triggered underconditions mimicking the CF patient airway.

Triazoles and aromatase: The impact of copper cocktails

Triazoles are used as antifungal agents, they mostly inhibit two enzymes: 14α-demethylase and aromatase. These enzymes are utilised also in other species and therefore the affection in non-target species in the environment is expected as well. Besides, triazoles are often being applied in a mixture and they can also interact with other substances present. This study clarifies how three selected representative triazoles (tebuconazole, penconazole and cyproconazole) interact with each other (group effect) and in mixtures (cocktail effect) with copper, essential/toxic for all organisms. Within the experiments on electrospray and collision-induced dissociations (both ESI-MS), it has been found that the fragments correspond to typical triazole metabolites. For their formation, the presence of copper ions is crucial. The inhibitory effect of Cu cocktails on aromatase enzymatic activity has been studied. The presence of Cu ions together with triazole(s) significantly increases the inhibitory effect on aromatase activity. The highest inhibitory effect (more than 60%) on aromatase activity is produced by cocktails containing penconazole and Cu ions, namely by penconazole/Cu and penconazole/tebuconazole/Cu. The reactivity of triazoles in groups is not significantly affected by the interactions among them. Additionally, the role of triazoles in copper Fenton reaction regulation has been observed and described. These changes may be attributed to the formation and stabilization of the complexes with the central Cu ion, with usually one, two or three triazolic ligands, depending on the mixture. The study demonstrates that the interaction of triazoles and Cu ions is a complex process; their impact on metabolism seems to be rather extensive and must be evaluated in the context of biochemical reactions.

Mucormycosis treatment: Recommendations, latest advances, and perspectives

Mucormycosis are life-threatening fungal infections especially affecting immunocompromised or diabetic patients. Despite treatment, mortality remains high (from 32 to 70% according to organ involvement). This review provides an update on mucormycosis management. The latest recommendations strongly recommend as first-line therapy the use of liposomal amphotericin B (≥5mg/kg) combined with surgery whenever possible. Isavuconazole and intravenous or delayed-release tablet forms of posaconazole have remained second-line. Many molecules are currently in development to fight against invasive fungal diseases but few have demonstrated efficacy against Mucorales. Despite in vitro efficacy, combinations of treatment have failed to demonstrate superiority versus monotherapy. Adjuvant therapies are particularly complex to evaluate without prospective randomized controlled studies, which are complex to perform due to low incidence rate and high mortality of mucormycosis. Perspectives are nonetheless encouraging. New approaches assessing relationships between host, fungi, and antifungal drugs, and new routes of administration such as aerosols could improve mucormycosis treatment.

How to interpret MICs of antifungal compounds according to the revised clinical breakpoints v. 10.0 European committee on antimicrobial susceptibility testing (EUCAST)

BACKGROUND

EUCAST has revised the definition of the susceptibility category I from 'Intermediate' to 'Susceptible, Increased exposure'. This implies that I can be used where the drug concentration at the site of infection is high, either because of dose escalation or through other means to ensure efficacy. Consequently, I is no longer used as a buffer zone to prevent technical factors from causing misclassifications and discrepancies in interpretations. Instead, an Area of Technical Uncertainty (ATU) has been introduced for MICs that cannot be categorized without additional information as a warning to the laboratory that decision on how to act has to be made. To implement these changes, the EUCAST-AFST (Subcommittee on Antifungal Susceptibility Testing) reviewed all, and revised some, clinical antifungal breakpoints.

OBJECTIVES

The aim was to present an overview of the current antifungal breakpoints and supporting evidence behind the changes.

SOURCES

This document is based on the ten recently updated EUCAST rationale documents, clinical breakpoint and breakpoint ECOFF documents.

CONTENT

The following breakpoints (in mg/L) have been revised or established for Candida species: micafungin against C. albicans (ATU = 0.03); amphotericin B (S ≤/> R = 1/1), fluconazole (S ≤/> R = 2/4), itraconazole (S ≤/> R = 0.06/0.06), posaconazole (S ≤/> R = 0.06/0.06) and voriconazole (S ≤/> R = 0.06/0.25) against C. dubliniensis; fluconazole against C. glabrata (S ≤/> R = 0.001/16); and anidulafungin (S ≤/> R = 4/4) and micafungin (S ≤/> R = 2/2) against C. parapsilosis. For Aspergillus, new or revised breakpoints include itraconazole (ATU = 2) and isavuconazole against A. flavus (S ≤/> R = 1/2, ATU = 2); amphotericin B (S ≤/> R = 1/1), isavuconazole (S ≤ /> R = 1/2, ATU = 2), itraconazole (S ≤/> R = 1/1, ATU = 2), posaconazole (ATU = 0.25) and voriconazole (S ≤/> R = 1/1, ATU = 2) against A. fumigatus; itraconazole (S ≤/> R = 1/1, ATU = 2) and voriconazole (S ≤/> R = 1/1, ATU = 2) against A. nidulans; amphotericin B against A. niger (S ≤/> R = 1/1); and itraconazole (S ≤/> R = 1/1, ATU = 2) and posaconazole (ATU = 0.25) against A. terreus.

IMPLICATIONS

EUCAST-AFST has released ten new documents summarizing existing and new breakpoints and MIC ranges for control strains. A failure to adopt the breakpoint changes may lead to misclassifications and suboptimal or inappropriate therapy of patients with fungal infections.

Retinoids and developmental neurotoxicity: Utilizing toxicogenomics to enhance adverse outcome pathways and testing strategies

The use of genomic approaches in toxicological studies has greatly increased our ability to define the molecular profiles of environmental chemicals associated with developmental neurotoxicity (DNT). Integration of these approaches with adverse outcome pathways (AOPs), a framework that translates environmental exposures to adverse developmental phenotypes, can potentially inform DNT testing strategies. Here, using retinoic acid (RA) as a case example, we demonstrate that the integration of toxicogenomic profiles into the AOP framework can be used to establish a paradigm for chemical testing. RA is a critical regulatory signaling molecule involved in multiple aspects of mammalian central nervous system (CNS) development, including hindbrain formation/patterning and neuronal differentiation, and imbalances in RA signaling pathways are linked with DNT. While the mechanisms remain unresolved, environmental chemicals can cause DNT by disrupting the RA signaling pathway. First, we reviewed literature evidence of RA and other retinoid exposures and DNT to define a provisional AOP related to imbalances in RA embryonic bioavailability and hindbrain development. Next, by integrating toxicogenomic datasets, we defined a relevant transcriptomic signature associated with RA-induced developmental neurotoxicity (RA-DNT) in human and rodent models that was tested against zebrafish model data, demonstrating potential for integration into an AOP framework. Finally, we demonstrated how these approaches may be systematically utilized to identify chemical hazards by testing the RA-DNT signature against azoles, a proposed class of compounds that alters RA-signaling. The provisional AOP from this study can be expanded in the future to better define DNT biomarkers relevant to RA signaling and toxicity.

Antifungal therapeutic drug monitoring: focus on drugs without a clear recommendation

BACKGROUND

The goal of therapeutic drug monitoring (TDM) is to determine the appropriate exposure of difficult-to-manage medications to optimize the clinical outcomes in patients in various clinical situations. Concerning antifungal treatment, and knowing that this procedure is expensive and time-consuming, TDM is particularly recommended for certain systemic antifungals: i.e., agents with a well-defined exposure-response relationship and unpredictable pharmacokinetic profile or narrow therapeutic index. Little evidence supports the routine use of TDM for polyenes (amphotericin B), echinocandins, fluconazole or new azoles such as isavuconazole, despite the fact that a better understanding of antifungal exposure may lead to a better response.

AIMS

The aim of this work is to review published pharmacokinetic/pharmacodynamic data on systemically administered antifungals, focusing on those for which monitoring is not routinely recommended by experts.

SOURCES

A MEDLINE search of the literature in English was performed introducing the following search terms: amphotericin B, fluconazole, itraconazole, voriconazole, posaconazole, triazoles, caspofungin, micafungin, anidulafungin, echinocandins, pharmacokinetics, pharmacodynamics, and therapeutic drug monitoring. Review articles and guidelines were also screened.

CONTENT

This review collects different pharmacokinetic/pharmacodynamic aspects of systemic antifungals and summarizes recent threshold values for clinical outcomes and adverse events. Although for polyenes, echinocandins, fluconazole and isavuconazole extensive clinical validation is still required for a clear threshold and a routine monitoring recommendation, particular points such as liposome structure or complex pathophysiological conditions affecting final exposure are discussed. For the rest, their better-defined exposure-response/toxicity relationships allow access to useful threshold values and to justify routine monitoring. Additionally, clinical data are needed to better define thresholds that can minimize the development of antifungal resistance.

IMPLICATIONS

General TDM for all systemic antifungals is not recommended; however, this approach may help to establish an adequate antifungal exposure for a favourable response, prevention of toxicity or development of resistance in special clinical circumstances.