The transcription factor Ofi1 is critical for white-opaque switching in natural MTLa/α isolates of Candida albicans.

Candida albicans, an opportunistic fungal pathogen, is able to switch between two distinct cell types: white and opaque. While white-to-opaque switching is typically repressed by the a1/α2 heterodimer in MTLa/α cells, it was recently reported that switching can also occur in some natural MTLa/α strains under certain environmental conditions. However, the regulatory program governing white-opaque switching in MTLa/α cells is not fully understood. Here, we collected 90 clinical isolates of C. albicans, 16 of which possess the ability to form opaque colonies. Among the known regulators implicated in white-opaque switching, only OFI1 exhibited significantly higher expression in these 16 strains compared to the reference strain SC5314. Importantly, ectopic expression of OFI1 in both clinical isolates and laboratory strains promoted switching frequency even in the absence of N-acetylglucosamine and high CO2 , the optimal condition for white-to-opaque switching in MTLa/α strains. Deleting OFI1 resulted in a reduction in opaque-formation frequency and the stability of the opaque cell in MTLa/α cells. Ofi1 binds to the promoters of WOR1 and WOR3 to induce their expression, which facilitates white-to-opaque switching. Ofi1 is conserved across the CTG species. Altogether, our study reported the identification of a transcription factor Ofi1 as the critical regulator that promotes white-to-opaque switching in natural MTLa/α isolates of C. albicans.

Zcf24, a zinc-finger transcription factor, is required for lactate catabolism and inhibits commensalism in Candida albicans.

Candida albicans is a normal resident of humans and also a prevalent fungal pathogen. Lactate, a nonfermentative carbon source available in numerous anatomical niches, can be used by C. albicans as a carbon source. However, the key regulator(s) involved in this process remain unknown. Here, through a genetic screen, we report the identification of a transcription factor Zcf24 that is specifically required for lactate utilization in C. albicans. Zcf24 is responsible for the induction of CYB2, a gene encoding lactate dehydrogenase that is essential for lactate catabolism, in response to lactate. Chromatin immunoprecipitation showed a significantly higher signal of Zcf24 on the CYB2 promoter in lactate-grown cells than that in glucose-grown cells. Genome-wide transcription profiling indicates that, in addition to CYB2, Zcf24 regulates genes involved in the ß-oxidation of fatty acids, iron transport, and drug transport. Surprisingly, deleting ZCF24 confers enhanced commensal fitness. This could be attributed to Crz1-activated ß-glucan masking in the zcf24 mutant. The orthologs of Zcf24 are distributed in species most closely to C. albicans and some filamentous fungal species. Altogether, Zcf24 is the first transcription factor identified to date that regulates lactate catabolism in C. albicans and it is also involved in the regulation of commensalism.

Epidemiologic features and therapeutic strategies of kerion: A nationwide multicentre study.

BACKGROUND: Kerion is a severe type of tinea capitis that is difficult to treat and remains a public health problem. OBJECTIVES: To evaluate the epidemiologic features and efficacy of different treatment schemes from real-world experience. METHODS: From 2019 to 2021, 316 patients diagnosed with kerion at 32 tertiary Chinese hospitals were enrolled. We analysed the data of each patient, including clinical characteristics, causative pathogens, treatments and outcomes. RESULTS: Preschool children were predominantly affected and were more likely to have zoophilic infection. The most common pathogen in China was Microsporum canis. Atopic dermatitis (AD), animal contact, endothrix infection and geophilic pathogens were linked with kerion occurrence. In terms of treatment, itraconazole was the most applied antifungal agent and reduced the time to mycological cure. A total of 22.5% of patients received systemic glucocorticoids simultaneously, which reduced the time to complete symptom relief. Furthermore, glucocorticoids combined with itraconazole had better treatment efficacy, with a higher rate and shorter time to achieving mycological cure. CONCLUSIONS: Kerion often affects preschoolers and leads to serious sequelae, with AD, animal contact, and endothrix infection as potential risk factors. Glucocorticoids, especially those combined with itraconazole, had better treatment efficacy.

Discovery of potential RIPK1 inhibitors by machine learning and molecular dynamics simulations.

Receptor-interacting serine/threonine-protein kinase 1 (RIPK1) plays a crucial role in inflammation and cell death, so it is a promising candidate for the treatment of autoimmune, inflammatory, neurodegenerative, and ischemic diseases. So far, there are no approved RIPK1 inhibitors available. In this study, four machine learning algorithms were employed (random forest, extra trees, extreme gradient boosting and light gradient boosting machine) to predict small molecule inhibitors of RIPK1. The statistical metrics revealed similar performance and demonstrated outstanding predictive capabilities in all four models. Molecular docking and clustering analysis were employed to confirm six compounds that are structurally distinct from existing RIPK1 inhibitors. Subsequent molecular dynamics simulations were performed to evaluate the binding ability of these compounds. Utilizing the Shapley additive explanation (SHAP) method, the 1855 bit has been identified as the most significant molecular fingerprint fragment. The findings propose that these six small molecules exhibit promising potential for targeting RIPK1 in associated diseases. Notably, the identification of Cpd-1 small molecule (ZINC000085897746) from the Musa acuminate highlights its natural product origin, warranting further attention and investigation.

A Workflow Combining Machine Learning with Molecular Simulations Uncovers Potential Dual-Target Inhibitors against BTK and JAK3.

The drug development process suffers from low success rates and requires expensive and time-consuming procedures. The traditional one drug-one target paradigm is often inadequate to treat multifactorial diseases. Multitarget drugs may potentially address problems such as adverse reactions to drugs. With the aim to discover a multitarget potential inhibitor for B-cell lymphoma treatment, herein, we developed a general pipeline combining machine learning, the interpretable model SHapley Additive exPlanation (SHAP), and molecular dynamics simulations to predict active compounds and fragments. Bruton's tyrosine kinase (BTK) and Janus kinase 3 (JAK3) are popular synergistic targets for B-cell lymphoma. We used this pipeline approach to identify prospective potential dual inhibitors from a natural product database and screened three candidate inhibitors with acceptable drug absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties. Ultimately, the compound CNP0266747 with specialized binding conformations that exhibited potential binding free energy against BTK and JAK3 was selected as the optimum choice. Furthermore, we also identified key residues and fingerprint features of this dual-target inhibitor of BTK and JAK3.

Synergistic Effect of the Combination of Deferoxamine and Fluconazole In Vitro and In Vivo against Fluconazole-Resistant Candida Spp.

The opportunistic fungal infections are an increasing threat to humans due to the increasing number of patients with immunodeficiency, in which the most popular fungal pathogen is Candida albicans. Fluconazole (FLC) is the common drug for treating C. albicans infections, but increasing drug resistance has limited its clinical use. Currently, combination therapy is being investigated as a treatment to overcome the resistance of C. albicans. This report investigated the synergistic properties of deferoxamine (DFO) and FLC combination therapy in vitro and in vivo against drug-resistant C. albicans. The results showed that the combination of DFO and FLC had a great synergistic antifungal effect against C. albicans, an FLC-resistant strain, with a fractional inhibition concentration index (FICI) of 0.25 by the broth microdilution checkerboard assay. Furthermore, the combination of DFO and FLC significantly inhibited the activity of C. glabrata cells (approximately 30% of C. glabrata cells are azole-resistant). The time-growth curves confirmed that the combination of DFO and FLC have a potent synergistic antifungal effect. Hyphal formation assays confirmed that DFO inhibited the hyphal induction of C. albicans. In addition, the combination of DFO and FLC significantly inhibited the expression of the adhesion gene (ALS1). In vivo experiments showed that the combination of DFO and FLC significantly reduced pustules, CFU counts and inflammatory cell infiltration in skin tissue. These results suggest that the combination of DFO and FLC inhibits yeast-hyphae transformation, reduces C. albicans infectivity and resistance in vitro and in vivo, and affects Cek1 MAPK signaling. This may offer a new option for the treatment of cutaneous candidiasis.

Inhibiting Fungal Echinocandin Resistance by Small-Molecule Disruption of Geranylgeranyltransferase Type I Activity.

Echinocandin resistance in Candida is a great concern, as the echinocandin drugs are recommended as first-line therapy for patients with invasive candidiasis. However, therapeutic efforts to thwart echinocandin resistance have been hampered by a lack of fungal specific drug targets. Here, we show that deleting CDC43, the ß subunit of geranylgeranyltransferase type I (GGTase I), confers hypersensitivity to echinocandins, which renders GGTase I a tractable target in combatting echinocandin resistance. The membrane localization of Rho1, which is critical for (1,3)-ß-d-glucan synthase Fks1 activation, is disrupted in the cdc43 mutant, resulting in decreased amounts of glucans in the cell wall, thereby exacerbating the cell wall stress upon caspofungin addition. Guided by this insight, we found that selective chemical inhibition of GGTase I by L-269289 potentiates echinocandin activity and renders echinocandin-resistant Candida albicans responsive to treatment in vitro and in animal models for disseminated infection. Furthermore, L-269289 and echinocandins also act in a synergistic manner for the treatment of Candida tropicalis and Candida parapsilosis Importantly, deletion of CDC43 is lethal in Candida glabrata L-269289 is active on its own to kill C. glabrata, and its fungicidal activity is enhanced when combined with caspofungin. Thus, targeting GGTase I has therapeutic potential to address the clinical challenge of echinocandin-resistant candidiasis.

The combined utilization of Chlorhexidine and Voriconazole or Natamycin to combat Fusarium infections.

BACKGROUND: Fusarium species are the fungal pathogens most commonly responsible for the mycotic keratitis, which are resistant to the majority of currently available antifungal agents. The present study was designed to assess the efficacy of a combination of low doses chlorhexidine with two other commonly used drugs (voriconazole and natamycin) to treat Fusarium infections. RESULTS: We utilized combinations of chlorhexidine and natamycin or voriconazole against 20 clinical Fusarium strains in vitro using a checkerboard-based microdilution strategy. In order to more fully understand the synergistic interactions between voriconazole and chlorhexidine, we utilized a Galleria mellonella model to confirm the combined antifungal efficacy of chlorhexidine and voriconazole in vivo. We found that for voriconazole, natamycin, and chlorhexidine as single agents, the minimum inhibitory concentration (MIC) ranges were 2-8, 4-16, and > 16 µg/ml, respectively. In contrast, the MIC values for voriconazole and chlorhexidine were reduced to 0.25-1 and 1-2 µg/ml, respectively, when these agents were administered in combination, with synergy being observed for 90% of tested Fusarium strains. Combined chlorhexidine and natamycin treatment, in contrast, exhibited synergistic activity for only 10% of tested Fusarium strains. We observed no evidence of antagonism. Our in vivo model results further confirmed the synergistic antifungal activity of chlorhexidine and voriconazole. CONCLUSIONS: Our results offer novel evidence that voriconazole and chlorhexidine exhibit synergistic activity when used to suppress the growth of Fusarium spp., and these agents may thus offer value as a combination topical antifungal treatment strategy.

A case of Tinea Faciei caused by Trichophyton benhamiae: first report in China.

BACKGROUND: Trichophyton benhamiae is a zoophilic dermatophyte that can cause tinea in humans and animals. Lesions caused by T. benhamiae tend to be highly inflammatory, and patients are often infected by animals or other patients infected with T. benhamiae. In this paper, we report the first case of tinea faciei caused by T. benhamiae in a Chinese girl who might be transmitted from a fox. CASE PRESENTATION: A 4-year-old girl from HaiNing city developed an itchy, erythematous, and annular plaque on her right face for the past 2 months. Before the lesion appeared, she was in close contact with the fur of a fox for almost 1 week. Septate hyaline hyphae were detected by direct mycological examination of the scales. Cultures grew on Sabouraud's dextrose agar (SDA) at 26 °C for 2 weeks revealed the presence of T. mentagrophytes. A molecular sequencing test confirmed that the isolate was consistent with reference strains to T. benhamiae. Then, the diagnosis of tinea faciei due to T. benhamiae was made. Treatment with terbinafine (oral 125 mg/d) and sertaconazole nitrate cream (topical, twice daily) for 4 weeks was initiated and achieved significant improvement of the skin lesions. CONCLUSIONS: This rare dermatophytosis case highlights the importance of ITS sequencing in helping to recognize rare pathogenic fungi that can be easily misdiagnosed with a conventional morphological diagnosis.

Aetiology of superficial fungal infections of the foot in urban outpatients in mainland China: A multicentre, prospective case study.

BACKGROUND: In China, the prevalence of superficial fungal infections of the foot is high and recurrence is common. However, a prospective, large-scale and multicentre study on the aetiology of superficial fungal infections of the foot is still lacking. OBJECTIVES: To study the epidemiology of aetiological agents of superficial fungal infections of the foot in urban outpatients in mainland China, as well as to understand the aetiology features of the pathogenic agent. METHODS: The study was designed as a multicentre, prospective epidemiological survey. A total of 1704 subjects were enrolled from seven geographical areas in mainland China. For each subject, one mycological sample and one bacterial sample were collected. KOH wet mount examination and culture were performed at local laboratories. The bacterial results were only reported in those with positive mycology. Further morphological identification and, if necessary, molecular biological identification were conducted in a central laboratory. RESULTS: Of 1704 enrolled subjects, 1327 (77.9%) subjects had positive fungal culture results. The incidence of dermatophytes, yeasts and moulds was 90.1%, 8.1% and 1.1%, respectively. The most frequently isolated aetiological agent (fungus) was Trichophyton rubrum. Moccasin form was the most commonly reported clinical diagnosis of superficial fungal infections. The most frequently isolated bacterial genus in patients was Staphylococcus. CONCLUSION: This study prospectively investigated the clinical and mycological features of human dermatophytosis in mainland China. T rubrum was the most frequently isolated fungus, and moccasin form was the most commonly reported clinical diagnosis of superficial fungal infections.

Subcutaneous granuloma caused by Kodamaea ohmeri in an immunocompromised patient in China.

We present a case of subcutaneous granuloma caused by Kodamaea ohmeri and describe the histopathological characteristics and skin lesions caused by this pathogen. A 55-year-old woman, with a history of rheumatoid arthritis, presented with red, painless plaque on her forehead, persistent for 3 months; based on the histopathological and mycological findings and gene sequencing, the patient was diagnosed with subcutaneous granuloma caused by K. ohmeri. This report highlights that early identification and diagnosis and optimal regimens are vital in the management of this intractable infection.

Inhibitory Effects of Photodynamic Inactivation on Planktonic Cells and Biofilms of Candida auris.

Candida auris is an emerging pathogen that has caused numerous severe infections in recent years, and has therefore become a global concern for public health agencies. Most conventional antifungal agents, especially fluconazole, have shown limited effects on this pathogen. New methods to restrict this pathogen are in urgent demand. Antimicrobial photodynamic therapy (aPDT) has been shown to be a promising technique against multiple pathogenic fungi. This study sought to determine the in vitro effect of aPDT using methylene blue (MB) combined with light-emitting diode (LED) on the viability of planktonic cells and biofilms of five clinical strains of C. auris. MB (8, 16 and 32 µg/ml) was applied as the photosensitizer, and a LED (635 nm, 12 and 24 J/cm2) device was used as light source to activate the photosensitizer. The results showed that there was no growth of tested C. auris strains following aPDT on planktonic cultures. In addition, aPDT exhibited colony-forming unit reduction of up to 7.20 log10 against C. auris biofilms. These data demonstrate that in vitro aPDT with MB and LED offers promising potential for the treatment of C. auris infections.

Characterization of Skin Microbiome in Tinea Pedis.

Tinea pedis has been associated with Trichophyton rubrum infection. However, it's not clear whether other microbes were implicated in disease pathogenesis. The composition of microbial communities of patients with tinea pedis and healthy controls were analyzed to identify the characteristics of tinea pedis and differences associated with clinical patterns. We found that microbial community structures were different in patients with tinea pedis compared with healthy controls. Moreover, skin microbiome varied in different forms of tinea pedis. Healthy controls exhibited greater fungal diversity than patients with tinea pedis. In patients with tinea pedis, the dominant bacterial and fungal genera were Staphylococcus and Trichophyton. Compared with healthy controls, Corynebacterium tuberculostearicum was decreased and T. rubrum was increased. C. tuberculostearicum was more abundant in vesicular tinea pedis than in hyperkeratotic and interdigital tinea pedis. Interdigital tinea pedis had a higher detection rate of Corynebacterium minutissimum and T. rubrum than the other forms. These results indicated that bacterial microbes may take part in the development of tinea pedis.

Subcutaneous Phaeohyphomycosis Caused by Exophiala oligosperma in an Immunocompetent Host: Case Report and Literature Review.

We report a case of subcutaneous infection caused by Exophiala oligosperma. Erythematous ulcerated plaque with exudate was major clinical features. Histopathological examination showed yeast-like cells and fungal hyphae. Mycological and molecular identification revealed E. oligosperma as etiologic agent. Local debridement and oral itraconazole were effective. To the best of our knowledge, this is the first report of phaeohyphomycosis caused by E. oligosperma in mainland China. This report highlights the potential role of E. oligosperma as an emerging cause of infection in immunocompetent patients.

Successful Sequential Treatment with Itraconazole and ALA-PDT for Cutaneous Granuloma by Candida albicans: A Case Report and Literature Review.

Photodynamic therapy (PDT) is a process that combines a photosensitizing drug and light and promotes phototoxic responses in target cells, mainly via oxidative damage. Antifungal photodynamic therapy has been successfully employed against Candida species, dermatophytes, and deep mycoses. We present a case of a cutaneous granuloma caused by C. albicans treated with 5-aminolevulinic acid (ALA)-PDT. A 64-year-old man presented with two plaques on his right hand and wrist for 2 years. The diagnosis was made based on histopathology, mycology, and molecular identification of paraffin-embedded tissues. The patient was treated with itraconazole for 1 month and two sessions of ALA-PDT. After 2 months of follow-up, the patient was cured and has not experienced any recurrence to date. ALA-PDT was well tolerated in this patient with little pain. In general, application of PDT in mycoses is safe and effective in most cases. ALA-PDT is a good choice for inactivation of C. albicans.

In situ photoimmunotherapy for cutaneous granuloma caused by itraconazole-resistant Candida guilliermondii.

Cutaneous granulomas caused by Candida guilliermondii are difficult to cure. In situ photoimmunotherapy (ISPI) is a novel method composed of local photothermal therapy and immunoadjuvant. In this study, ISPI was used the first time clinically for cutaneous granuloma caused by itraconazole-resistant C.guilliermondii. A 10-week cycle of ISPI was composed of (1) 5% imiquimod applied topically every other day and (2) irradiation of lesions with an 808-nm diode laser at Days 14, 28, 42, and 56. Here we report our first case. A patient was treated with ISPI for four cycles. After the treatment, the lesions were eliminated without recurrence during a 12-month follow-up. Our results demonstrate that ISPI can be used as an effective treatment modality for cutaneous fungal granuloma.

Case report: Subcutaneous Mycobacterium haemophilum infection in an immunocompetent patient after lipolysis injections.

Mycobacterium haemophilum is a slow-growing, aerobic mycobacterium that acts as a pathogen in immunocompromised adult patients and immunocompetent children. There are only a few rare cases in the literature describing this species as a cause of subcutaneous infections. Here, we describe a subcutaneous infection caused by M. haemophilum in an immunocompetent female after lipolysis injections at an unqualified beauty salon, suggesting that this bacteria can also be a potential causative agent of adverse events in medical aesthetics. In addition, M. haemophilum caused lesions not only at the injection sites and adjacent areas but also invaded distant sections through the subcutaneous sinus tracts. Thus, early diagnosis and appropriate treatment are vital to prevent further deterioration and improve prognosis.

Analysis of the synergistic antifungal activity of everolimus and antifungal drugs against dematiaceous fungi.

Introduction: Chromoblastomycosis (CBM) is a form of chronic mycosis that affects the skin and mucous membranes and is caused by species of dematiaceous fungi including Exophiala spp., Phialophora spp., and Fonsecaea spp. The persistence of this disease and limitations associated with single-drug treatment have complicated efforts to adequately manage this condition. Methods: In this study, a microdilution assay was used to explore the synergistic antifungal activity of everolimus (EVL) in combination with itraconazole (ITC), voriconazole (VRC), posaconazole (POS), and amphotericin B (AMB) against a range of clinical dematiaceous fungal isolates. Results: These analyses revealed that the EVL+POS and EVL+ITC exhibited superior in vitro synergistic efficacy, respectively inhibiting the growth of 64% (14/22) and 59% (13/22) of tested strains. In contrast, the growth of just 9% (2/22) of tested strains was inhibited by a combination of EVL+AMB, and no synergistic efficacy was observed for the combination of EVL+VRC. Discussion: Overall, these findings indicate that EVL holds promise as a novel drug that can be synergistically combined with extant antifungal drugs to improve their efficacy, thereby aiding in the treatment of CBM.

Inhibition mechanism understanding from molecular dynamics simulation of the interactions between several flavonoids and proton-dependent glucose transporter.

Proton-dependent glucose transporters as important drug targets can have different protonation states and adjust their conformational state under different pHs. So based on this character, research on its inhibition mechanism is a significant work. In this article, to study its inhibitory mechanism, we performed the molecular dynamics of several classical flavonoid molecules (Three inhibitors Phloretin, Naringenin, Resveratrol. Two non-inhibitors Isoliquiritigenin, Butein) with glucose transporters under two distinct environmental pHs. The results show inhibitors occupy glucose binding sites (GLN137, ILE255, ASN256) and have strong hydrophobic interactions with proteins through core moiety (C6-Cn-C6). In addition, inhibitors had better inhibitory effects in protonation state. In contrast, non-inhibitors can not occupy glucose binding sites (GLN137, ILE255, ASN256), thus they do not have intense interactions with the protein. It is suggested that favorable inhibitors should effectively take up the glucose-binding site (GLN137, ILE255, ASN256) and limit the protein conformational changes.Communicated by Ramaswamy H. Sarma.