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Abstract Background Candida glabrata is an important cause of invasive candidiasis. Echinocandins are the first-line treatment of invasive candidiasis caused by C. glabrata. The epidemiological echinocandin sensitivity requires long-term surveillance and the understanding about whole genome characteristics of echinocandin non-susceptible isolates was limited. Results The present study investigated the echinocandin susceptibility of 1650 C. glabrata clinical isolates in China from August 2014 to July 2019. The in vitro activity of micafungin was significantly better than those of caspofungin and anidulafungin (P

Introduction: The incidence of candidiasis can vary across various subsites within the head and neck region and is associated with various co-morbidities and risk factors. The increase in the incidence of resistant Non-albicans Candida (NAC) species among these patients and the limited number of available antifungal agents make treatment difficult. A better understanding of the subsite-specific prevalence of candidiasis and its antifungal susceptibility is crucial in enhancing effective control and treatment. Aim: To determine the subsite-specific prevalence of candidiasis among Head and Neck Cancer (HNC) patients undergoing radiotherapy. Materials and Methods: A cross-sectional study was conducted on patients undergoing therapy for head and neck malignancies at the Department of Radiation Oncology, Amala Institute of Medical Sciences, Thrissur, Kerala, India over a four-year period (January 2019 to December 2022). A total of 276 patients aged 18 to 85 years with squamous cell carcinoma were included. Oral samples were collected from patients who developed candidiasis, and co-morbidities and risk factors were documented. Candida species were isolated and identified. Antifungal susceptibility was determined using the VITEK system, and fluconazole susceptibility was compared with the standard disc diffusion method. Data were entered into an Excel sheet and analysed using Statistical Package for the Social Sciences (SPSS) software. Results: Pharynx was the most frequent site of head and neck malignancy, accounting for 104 cases (37.7%), followed by the oral cavity with 83 cases (30.1%). Among patients with malignancies in the pharyngeal region, a high rate of Candida infection was observed in 42 (43.3%) out of 97 cases. Candida species isolated included C. albicans (56, 57.7%), C. tropicalis (26, 26.8%), C. krusei (8, 8.3%), C. glabrata (3, 3.1%), and C. parapsilosis (4, 4.1%). Sixty-five patients (23.5%) had diabetes, which was statistically significant (p-value

Abstract Background Candida glabrata which belongs to normal microbiota, has caused significant concern worldwide due to its high prevalence and drug resistance in recent years. C. glabrata has developed many strategies to evade the clearance of the host immune system, thereby causing persistent infection. Although coping with the induced DNA damage is widely acknowledged to be important, the underlying mechanisms remain unclear. Results The present study provides hitherto undocumented evidence of the importance of the regulatory subunits of CgCK2 (CgCkb1 and CgCkb2) in response to DNA damage. Deletion of CgCKB1 or CgCKB2 enhanced cellular apoptosis and DNA breaks and led to cell cycle delay. In addition, deficiencies in survival upon phagocytosis were observed in Δckb1 and Δckb2 strains. Consistently, disruption of CgCKB1 and CgCKB2 attenuated the virulence of C. glabrata in mouse models of invasive candidiasis. Furthermore, global transcriptional profiling analysis revealed that CgCkb1 and CgCkb2 participate in cell cycle resumption and genomic stability. Conclusions Overall, our findings suggest that the response to DNA damage stress is crucial for C. glabrata to survive in macrophages, leading to full virulence in vivo. The significance of this work lies in providing a better understanding of pathogenicity in C. glabrata-related candidiasis and expanding ideas for clinical therapies.

Urinary tract infections (UTIs) associated with indwelling urinary catheterization (IUC) in premature newborns (PNBs) pose a significant challenge in neonatal intensive care units (NICUs) due to the vulnerability of this population to infections and the necessity of invasive procedures. While bacterial UTIs have historically been predominant, there is a rising incidence of fungal pathogens, particularly non-albicans Candida strains like Candida glabrata and Candida tropicalis, attributed to broad-spectrum antibiotic use. Diagnosis of fungal UTIs in a PNB relies on culturing Candida spp. from properly collected urine samples, particularly critical in very low birth weight (VLBW) PNBs because of the risk of invasive candidiasis and associated complications. We present a case of an extremely premature newborn (EPNB) successfully treated for a UTI caused by C. glabrata with micafungin. Our case exhibits micafungin as a potentially safe and effective alternative for treating C. glabrata UTIs in neonates.

Candida glabrata is an important pathogen causing invasive infection associated with a high mortality rate. One mechanism that causes the failure of Candida eradication is an increase in regulatory T cells (Treg), which play a major role in immune suppression and promoting Candida pathogenicity. To date, how C. glabrata induces a Treg response remains unclear. Dendritic cells (DCs) recognition of fungi provides the fundamental signal determining the fate of the T-cell response. This study investigated the interplay between C. glabrata and DCs and its effect on Treg induction. We found that C. glabrata β-glucan was a major component that interacted with DCs and consequently mediated the Treg response. Blocking the binding of C. glabrata β-glucan to dectin-1 and complement receptor 3 (CR3) showed that CR3 activation in DCs was crucial for the induction of Treg. Furthermore, a ligand–receptor binding assay showed the preferential binding of C. glabrata β-glucan to CR3. Our data suggest that C. glabrata β-glucan potentially mediates the Treg response, probably through CR3-dependent activation in DCs. This study contributes new insights into immune modulation by C. glabrata that may lead to a better design of novel immunotherapeutic strategies for invasive C. glabrata infection.

ABSTRACTRecent epidemiological studies documented an alarming increase in the prevalence of echinocandin-resistant (ECR) Candida glabrata blood isolates. ECR isolates are known to arise from a minor subpopulation of a clonal population, termed echinocandin persisters. Although it is believed that isolates with a higher echinocandin persistence (ECP) are more likely to develop ECR, the implication of ECP needs to be better understood. Moreover, replacing laborious and time-consuming traditional approaches to determine ECP levels with rapid, convenient, and reliable tools is imperative to advance our understanding of this emerging concept in clinical practice. Herein, using extensive ex vivo and in vivo systemic infection models, we showed that high ECP isolates are less effectively cleared by micafungin treatment and exclusively give rise to ECR colonies. Additionally, we developed a flow cytometry-based tool that takes advantage of a SYTOX-based assay for the stratification of ECP levels. Once challenged with various collections of echinocandin-susceptible blood isolates, our assay reliably differentiated ECP levels in vitro and predicted ECP levels in real time under ex vivo and in vivo conditions when compared to traditional methods relying on colony-forming unit counting. Given the high and low ECP predictive values of 92.3% and 82.3%, respectively, our assay showed a high agreement with traditional approach. Collectively, our study supports the concept of ECP level determination in clinical settings and provides a robust tool scalable for high-throughput settings. Application of this tool facilitates the interrogation of mutant and drug libraries to further our understanding of persister biology and designing anti-persister therapeutics.IMPORTANCECandida glabrata is a prevalent fungal pathogen able to replicate inside macrophages and rapidly develop resistance against frontline antifungal echinocandins. Multiple studies have shown that echinocandin resistance is fueled by the survival of a small subpopulation of susceptible cells surviving lethal concentrations of echinocandins. Importantly, bacterial pathogens that exhibit high antibiotic persistence also impose a high burden and generate more antibiotic-resistant colonies. Nonetheless, the implications of echinocandin persistence (ECP) among the clinical isolates of C. glabrata have not been defined. Additionally, ECP level determination relies on a laborious and time-consuming method, which is prone to high variation. By exploiting in vivo systemic infection and ex vivo models, we showed that C. glabrata isolates with a higher ECP are associated with a higher burden and more likely develop echinocandin resistance upon micafungin treatment. Additionally, we developed an assay that reliably determines ECP levels in real time. Therefore, our study identified C. glabrata isolates displaying high ECP levels as important entities and provided a reliable and convenient tool for measuring echinocandin persistence, which is extendable to other fungal and bacterial pathogens.

Introduction:Candida species are endowed with the ability to produce biofilms, which is one of the causes of pathogenicity, as biofilms protect yeasts from antifungal drugs. Candida glabrata (Nakaseomyces glabrata) is one of the most prevalent pathogenic yeasts in humans and a biofilm producer.Methods: The study was aimed at evaluating the combined effects of two highly promising antifungal biomolecules (AF4 and AF5) lipopeptide in nature, chromatographically purified to homogeneity from Bacillus subtilis (B. subtilis) and the standard antifungal fluconazole (at different concentrations) to demonstrate C. glabrata biofilm formation inhibition. Biofilm production and inhibition were evaluated by quantification of the biofilm biomass and metabolic activity using crystal violet (CV) staining and XTT reduction assays, respectively. Microscopic techniques such as confocal scanning laser microscopy (CSLM) and scanning electron microscopy (SEM) were employed to visualize biofilm formation and inhibition.Results and Discussion: Compared to untreated and fluconazole-treated biofilms, an enhanced in vitro anti-biofilm effect of the antifungal lipopeptides AF4/AF5 alone and their combinations with fluconazole was established. The lipopeptides AF4/AF5 alone at 8 and 16 μg/mL exhibited significant biomass and metabolic activity reductions. SEM and CSLM images provided evidence that the lipopeptide exposure results in architectural alterations and a significant reduction of C. glabrata biofilms, whereas (2′, 7′-dichlorofluorescin diacetate (DCFDA) and propidium iodide (PI) analyses showed reactive oxygen species (ROS) generation along with membrane permeabilization. The estimation of exopolysaccharides (EPS) in AF4/AF5-treated biofilms indicated EPS reduction. The combinations of fluconazole (64/128 μg/mL) and AF4/AF5 lipopeptide (16 μg/mL) were found to significantly disrupt the mature (24 h) biofilms as revealed by CSLM and SEM studies. The CSLM images of biofilms were validated using COMSTAT. The FTIR-analyses indicate the antibiofilm effects of both lipopeptides on 24 h biofilms to support CSLM and SEM observations. The combinations of fluconazole (64/128 μg/mL) and AF4/AF5 lipopeptide were found to disrupt the mature biofilms; the study also showed that the lipopeptides alone have the potentials to combat C. glabrata biofilms. Taken together, it may be suggested that these lipopeptide leads can be optimized to potentially apply on various surfaces to either reduce or nearly eradicate yeast biofilms.

Background and Objectives: The presence of fungi in the respiratory tract as mycobiome, particularly Candida species (spp.), remains a serious problem due to increasing numbers of immunocompromised pa-tients. The confirmed reliable existence of these pathogens due to frequent colonization is essential. This investigation aimed to recognize Candida spp. among isolates from bron-choalveolar lavage of immunocompromised and critically ill patients and to evaluate their susceptibility to antimycotic drugs. Materials and Methods: Bronchoalveolar lavage fluid was collected from 161 hospitalized patients presenting with suspected respiratory fungal infection /colonization. The specimens were examined by standard molecular and mycological assays. Candida spp. were recognized with sequence assessment of the D1-D2 section of the large subunit ribosomal DNA. The susceptibility of Candida isolates to common antimycotic drugs was distinguished by standard broth micro-dilution. Results: Seventy-one clinical isolates of Candida spp. were recognized. Candida albicans was the most frequent, followed by C. glabrata, C. krusei (Pichia kudriavzevii), C. dubliniensis, C. parapsilosis, and C. tropicalis. We found 5.1% of C. albicans isolates and 8% of C. glabrata isolates to show resistance to fluconazole. The whole of the Candida spp. were sensitive to amphotericin B and caspofungin. Conclusion: This study demonstrated that C. albicans and C. glabrata are the most common isolates of bronchoalveolar lavage fluid in patients, and the drug susceptibility screening confirmed that amphotericin B and caspofungin are effective against Candida spp. but some C. glabrata and C. albicans isolates showed resistance to fluconazole.

Herein, we report a case of pancreatic cancer with acute cholangitis secondary to biliary obstruction. Empirical antibiotic therapy did not change the clinical presentation. Blood cultures were sterile; however, bile culture was positive for yeasts. Our laboratory analysis revealed a biliary coinfection by multidrug-resistant C. glabrata and C. albicans. The patient was successfully treated with endoscopic biliary drainage.

We report on a 64-year-old man with necrotizing pancreatitis related, invasive candidiasis, and candidemia. Despite a multidisciplinary management including antifungal therapy, endoscopic interventions and surgery, the patients’ infection progressed and lead to colon perforation, retroperitoneal abscess formation, and polymicrobial bloodstream infections. Resistance to echinocandins in Candida glabrata further complicated the course. This report emphasizes the need for vigilant monitoring and exploring alternative therapeutic approaches for patients in critical conditions.

Infections caused by Candida species increased, as well as species resistant to the most conventional antimicrobials. Thus, the search for new natural sources of antimicrobials without adverse effects also increased. In this case, Astronium urundeuva Engl., a medicinal plant with several pharmacological activities, including antifungal activity, emerges as a source of antifungal compounds. Here, we evaluated the antifungal activity of A. urundeuva and its derivatives free or loaded into a nanostructured lipid system and combination studies against Candida species. A. urundeuva component's purification and identification were performed through chromatographic and spectroscopic techniques, respectively. The major components identified were gallic acid (1), methyl gallate (2), ethyl gallate (3), and 1,2,3,4,6-penta-O-galoyl-β-D-glucose (PGG) (4). A. urundeuva extract, its aqueous fraction, and PGG (4) exhibited the same MIC values between 0.2 and 62.5 µg/mL against Candida species being classified as significant activity, while the amphotericin B MIC was 0.1–1.2 µg/mL. Combination assay demonstrated that may occur synergism (0.37) between gallic acid (1) x methyl gallate (2). Thus, the results demonstrated as PGG (4) much as the gallic acid (1) x methyl gallate (2) combined might be the main responsible for the antifungal activity against Candida species, mainly Candida glabrata ATCC 2001 and that the tested nanostructured system maintained the antifungal activity. Through the antifungal activity of the extract and purified compounds, the extract may be employed in the development of antifungal herbal medicine, because its purification process is simple and greener than pure compounds. [ABSTRACT FROM AUTHOR]

Followed by Candida albicans, Candida glabrata ranks as the second major species contributing to invasive candidiasis. Given the higher medical burden and lower susceptibility to azoles in C. glabrata infections, identifying these infections is critical. From 2016 to 2021, patients with deep-seated candidiasis due to C. glabrata and non- glabrata Candida met the criteria to be enrolled in the study. Clinical data were randomly divided into training and validation cohorts. A predictive model and nomogram were constructed using R software based on the stepwise algorithm and logistic regression. The performance of the model was assessed by the area under the receiver operating characteristic curve and decision curve analysis (DCA). A total of 197 patients were included in the study, 134 of them infected with non- glabrata Candida and 63 with C. glabrata. The predictive model for C. glabrata infection consisted of gastrointestinal cancer, co-infected with bacteria, diabetes mellitus, and kidney dysfunction. The specificity was 84.1% and the sensitivity was 61.5% in the validation cohort when the cutoff value was set to the same as the training cohort. Based on the model, treatment for patients with a high-risk threshold was better than 'treatment for all' in DCA, while opting low-risk patients out of treatment was also better than 'treatment for none' in opt-out DCA. The predictive model provides a rapid method for judging the probability of infections due to C. glabrata and will be of benefit to clinicians making decisions about therapy strategies. [ABSTRACT FROM AUTHOR]

Candida glabrata is the most common non-albicans Candida species that causes vulvovaginal candidiasis (VVC). Given the intrinsically low susceptibility of C. glabrata to azole drugs, investigations into C. glabrata prevalence, fungal susceptibility profile, and molecular epidemiology are necessary to optimise the treatment of VVC. This molecular epidemiological study was conducted to determine antifungal drug profile, single nucleotide polymorphisms (SNPs) associated with phenotypic antifungal resistance and epidemic diversity of C. glabrata isolates from women with VVC in Namibia. Candida glabrata isolates were identified using phenotypic and molecular methods. Antifungal susceptibility of strains was determined for fluconazole, itraconazole, amphotericin B, and anidulafungin. Whole genome sequencing was used to determine SNPs in antifungal resistance genes and sequence type (ST) allocation. Among C. glabrata isolates, all (20/20; 100%) exhibited phenotypic resistance to the azole class antifungal drug, (fluconazole), and phenotypic susceptibility to the polyene class (amphotericin B), and the echinocandins (anidulafungin). Non-synonymous SNPs were identified in antifungal resistance genes of all fluconazole-resistant C. glabrata isolates including ERG6 (15%), ERG7 (15%), CgCDR1 (25%) , CgPDR1 (60%) , SNQ2 (10%) , FKS1 (5.0%) , FKS2 (5.0%) , CgFPS1 (5.0%), and MSH2 (15%). ST15 (n  = 8/20, 40%) was predominant. This study provides important insight into phenotypic and genotypic antifungal resistance across C. glabrata isolates from women with VVC in Namibia. In this study, azole resistance is determined by an extensive range of SNPs, while the observed polyene and echinocandin resistance-associated SNPs despite phenotypic susceptibility require further investigation. [ABSTRACT FROM AUTHOR]

Introduction: Candida glabrata has emerged as a fungal pathogen with high infection and mortality rates, and its primary virulence factors are related to adhesion and biofilm formation. These virulence factors in C.glabrata are primarily mediated by epithelial adhesins (Epas), most of which are encoded in subtelomeric regions and regulated by subtelomeric silencing mechanisms. The transcription factor Mss11, known for its regulatory role in adhesion, biofilm formation, and filamentous growth in Saccharomyces cerevisiae and Candida albicans, has also been implicated in the expression of EPA6, suggesting its potential influence on C.glabrata virulence. The present study aims to determine the regulatory role of Mss11 in the virulence of C. glabrata. Methods: In this work, a Δmss11 null mutant and its complemented strain were constructed from a C.glabrata standard strain. The impact of the transcription factor Mss11 on the virulence of C.glabrata was investigated through a series of phenotypic experiments, including the microbial adhesion to hydrocarbons (MATH) test, adherence assay, biofilm assay, scanning electron microscopy and Galleria mellonella virulence assay. Furthermore, transcriptome sequencing, quantitative reverse transcription polymerase chain reaction (RT-qPCR), and chromatin immunoprecipitation sequencing (ChIP-seq) were employed to investigate the molecular mechanisms behind the regulation of Mss11. Results: In C.glabrata, the loss of MSS11 led to a significant reduction in several virulence factors including cell surface hydrophobicity, epithelial cell adhesion, and biofilm formation. These observations were consistent with the decreased virulence of the Δmss11 mutant observed in the Galleria mellonella infection model. Further exploration demonstrated that Mss11 modulates C. glabrata virulence by regulating EPA1 and EPA6 expression. It binds to the upstream regions of EPA1 and EPA6, as well as the promoter regions of the subtelomeric silencing-related genes SIR4, RIF1, and RAP1, indicating the dual regulatory role of Mss11. Conclusion: Mss11 plays a crucial role in C. glabrata adhesion and biofilm formation, and thus has a broad influence on virulence. This regulation is achieved by regulating the expression of EPA1 and EPA6 through both promoter-specific regulation and subtelomeric silencing. [ABSTRACT FROM AUTHOR]

Most previous studies on fungal NADPH oxidases (Nox) focused on multicellular fungi and highlighted the important roles of Nox-derived reactive oxygen species (ROS) in cellular differentiation and signaling communication. However, there are few reports about Nox in unicellular fungi. A novel NOX ortholog, CAGL0K05863g (named CgNOX1), in Candida glabrata was investigated in this study. Deletion of CgNOX1 led to a decrease in both intracellular and extracellular ROS production. In addition, the Cgnox1∆ mutant exhibited hypersensitivity to hydrogen peroxide and menadione. Also, the wild-type strain showed higher levels of both CgNOX1 mRNA expression and ROS production under oxidative stress. Moreover, the absence of CgNOX1 resulted in impaired ferric reductase activity. Although there was no effect on in vitro biofilm formation, the CgNOX1 mutant did not produce hepatic apoptosis, which might be mediated by fungal Nox-derived ROS during co-incubation. Together, these results indicated that the novel NOX gene plays important roles in unicellular pathogenic C. glabrata and its interaction with host cells. [ABSTRACT FROM AUTHOR]

Drug-resistant microbes typically carry mutations in genes involved in critical cellular functions and may therefore be less fit under drug-free conditions than susceptible strains. Candida glabrata is a prevalent opportunistic yeast pathogen with a high rate of fluconazole resistance (FLZR), echinocandin resistance (ECR), and multidrug resistance (MDR) relative to other Candida. However, the fitness of C. glabrata MDR isolates, particularly in the host, is poorly characterized, and studies of FLZR isolate fitness have produced contradictory findings. Two important host niches for C. glabrata are macrophages, in which it survives and proliferates, and the gut. Herein, we used a collection of clinical and lab-derived C. glabrata isolates to show that FLZR C. glabrata isolates are less fit inside macrophages than susceptible isolates and that this fitness cost is reversed by acquiring ECR mutations. Interestingly, dual-RNAseq revealed that macrophages infected with drug-resistant isolates mount an inflammatory response whereas intracellular drug-resistant cells downregulate processes required for in-host adaptation. Furthermore, drug-resistant isolates were outcompeted by their susceptible counterparts during gut colonization and in infected kidneys, while showing comparable fitness in the spleen. Collectively, our study shows that macrophage-rich organs, such as the spleen, favor the retention of MDR isolates of C. glabrata. [ABSTRACT FROM AUTHOR]

Aims Candidiasis is the most opportunistic infection with a high rate of recurrent infection. Salvia macrosiphon has an antibacterial effect; however, its antifungal effect was not studied. This study aimed to investigate the chemical composition of essential oil from leaves of Salvia macrosiphon and its antifungal activity compared with fluconazole. Materials & Methods Salvia macrosiphon leaves, a native plant of Kogiluyeh and Boyerahmad province, were collected from Zagros Heights and used in this study. Then, the essential oil of this plant was tested for antibacterial and antifungal properties and compared with fluconazole. The chemical composition of the essential oil was analyzed by GC/MS (Gas Chromatography Mass Spectrometry), and the antifungal activity of the plant’s essential oil was compared with that of fluconazole. Findings The results of GC-MS analysis proved the presence of at least 29 compounds in the essential oil of Salvia macrosiphon. Amon these constitute butyl benzoate (49.16%), n-hexyl benzoate (7%), and isopatolenol (4.83%) were the main compounds. The minimum inhibitory concentration (MIC) of the essential oil (μl/ml) of Salvia macrosiphon and fluconazole (μg/ ml) were 0.44 and 0.7 for Candida albicans, 0.056 and 0.7 for C. glabrata, and 0.1 and 0.088 for C. parapsilosis, respectively. Also, statistical analysis demonstrated a significant difference between the mean of fluconazole and essential oil in total Candida isolates (p=0.001). Conclusion The essential oil of Salvia macrosiphon has stronger antifungal activity than fluconazole. [ABSTRACT FROM AUTHOR]

The growing threat of antimicrobial resistance (AMR) is a global concern. With AMR directly causing 1.27 million deaths in 2019 and projections of up to 10 million annual deaths by 2050, optimising infectious disease treatments is imperative. Prudent antimicrobial use, including treatment duration, can mitigate AMR emergence. This is particularly critical in candidemia, a severe condition with a 45% crude mortality rate, as the 14-day minimum treatment period has not been challenged in randomised comparison. A comprehensive literature search was conducted in August 2023, revealing seven original articles and two case series discussing treatment durations of less than 14 days for candidemia. No interventional trials or prospective observational studies assessing shorter durations were found. Historical studies showed varying candidemia treatment durations, questioning the current 14-day minimum recommendation. Recent research observed no significant survival differences between patients receiving shorter or longer treatment, emphasising the need for evidence-based guidance. Treatment duration reduction post-blood culture clearance could decrease exposure to antifungal drugs, limiting selection pressure, especially in the context of emerging multiresistant Candida species. Candidemia's complexity, emerging resistance and potential for shorter in-hospital stays underscore the urgency of refining treatment strategies. Evidence-driven candidemia treatment durations are imperative to balance efficacy with resistance prevention and ensure the longevity of antifungal therapies. Further research and clinical trials are needed to establish evidence-based guidelines for candidemia treatment duration. [ABSTRACT FROM AUTHOR]

Background and Aim: Side effects associated with antimicrobial drugs, as well as their high cost, have stimulated the search for inexpensive herbal medicinals with fewer side effects. These substances can be used as a medicinal supplement or to increase the antimicrobial and antifungal effects of drugs. The aim of this study is to investigate the inhibitory effect of oleuropein on fungal and bacterial pathogens isolated from nail infection in laboratory condition. Methods: Antifungal and antibacterial properties of oleuropein by determining the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Minimum Fungicidal Concentration (MFC) of this substance on yeasts Candida albicans, Candida glabrata and Escherichia coli by microbroth dilution method using CLSI protocols were evaluated. Results: The results showed that the Minimum Inhibitory Concentration (MIC) against all three studied microorganisms was equal to 65 mg/ml and the Minimum Bactericidal Concentration (MBC) and Minimum Fungicidal Concentration (MFC) of oleuropein was equal to 130 mg/ml. Conclusion: due to the high antifungal and antibacterial activity of oleuropein, the present study introduces oleuropein as a natural antimicrobial drug. This substance can also be used to increase the antimicrobial power of existing antibiotics. [ABSTRACT FROM AUTHOR]

Purpose: Oral candidiasis is one of the most common fungal opportunistic infections in the mouth caused by a fungus called Candida, and it presents as commensals in all humans. Over the last few decades, the increasing incidence of Candida infections parallels the growing numbers of immunocompromised patients. This trend is aggravated by the fact that there is a reckless use of antifungals. To combat this trend, the use of natural antifungals which have fewer side effects is recommended. Black grape seed extract (GSE) has shown a promise in this regard. Materials and Methods: Candida species such as Candida krusei, Candida glabrata, Candida tropicalis, and Candida albicans were used in the study. Fungal strains were passaged in the agar Sabouraud dextrose environment from 24 h to have live and fresh strains for the test. Black GSE was obtained. Minimum inhibitory concentration (MIC), of GSE, amphotericin B and fluconazole drugs on the included fungi was examined using disc diffusion method. Then, the plates were incubated for 24 h at 37°C. Finally, growth inhibitory zone was examined. Results: The analysis of the results revealed that the growth of C. albicans and C. krusei had been stopped at the concentration of 6.25 μg/mL, but the growth of C. glabrata and C. tropicalis was inhibited at a concentration of 12.25 μg/mL and 0.8 μg/mL respectively. Conclusion: The results obtained from the present study showed that both disc diffusion method and the maximum inhibitory concentration of MIC (Macro dilution) confirms the antimicrobial susceptibility of four species of candida to GSE. We conclude the possibility of GSE as an effective alternative measure for commercial antifungal agents, especially among immunocompromised patients, However, more laboratory and clinical studies need to be conducted to validate our findings. [ABSTRACT FROM AUTHOR]

Four different cold plasma sources were directly applied onto a 24h inoculum of Candida glabrata inoculated on agar plates, within the limits of in vitro experiment. Their effects were compared and evaluated with respect to the size and stability of the inhibition zones formed in the posttreatment cultivation. The results prove significant inhibitory cold atmospheric‐pressure plasma effects on the yeast C. glabrata. The overall inhibitory effects are directly proportional to the treatment time, the applied power, and the overall functioning of the plasma source and indirectly proportional to the initial cell concentration, although this factor was less significant compared to the other examined factors. The unipolar microwave torch was found to be the most effective in the inhibition of C. glabrata. [ABSTRACT FROM AUTHOR]

Background: To date, azoles represent the only viable option for oral treatment of invasive Candida infections, while rates of azole resistance among non-albicans Candida spp. continue to increase. The objective of this sub-analysis of the European multicenter observational cohort study Candida III was to describe demographical and clinical characteristics of the cohort requiring prolonged hospitalization solely to complete intravenous (iv) antifungal treatment (AF Tx). Methods: Each participating hospital (number of eligible hospitals per country determined by population size) included the first ~ 10 blood culture proven adult candidemia cases occurring consecutively after July 1st, 2018, and treating physicians answered the question on whether hospital stay was prolonged only for completion of intravenous antifungal therapy. Descriptive analyses as well as binary logistic regression was used to assess for predictors of prolonged hospitalization solely to complete iv AF Tx. Findings: Hospital stay was prolonged solely for the completion of iv AF Tx in 16% (100/621) of candidemia cases by a median of 16 days (IQR 8 – 28). In the multivariable model, initial echinocandin treatment was a positive predictor for prolonged hospitalization to complete iv AF Tx (aOR 2.87, 95% CI 1.55 – 5.32, p < 0.001), while (i) neutropenia, (ii) intensive care unit admission, (iii) catheter related candidemia, (iv) total parenteral nutrition, and (v) C. parapsilosis as causative pathogen were found to be negative predictors (aOR 0.22 – 0.45; p < 0.03). Interpretation: Hospital stays were prolonged due to need of iv AF Tx in 16% of patients with candidemia. Those patients were more likely to receive echinocandins as initial treatment and were less severely ill and less likely infected with C. parapsilosis. [ABSTRACT FROM AUTHOR]

The rising number of invasive fungal infections caused by drug-resistant Candida strains is one of the greatest challenges for the development of novel antifungal strategies. The scarcity of available antifungals has drawn attention to the potential of natural products as antifungals and in combinational therapies. One of these is catechins—polyphenolic compounds—flavanols, found in a variety of plants. In this work, we evaluated the changes in the susceptibility of Candida glabrata strain characterized at the laboratory level and clinical isolates using the combination of catechin and antifungal azoles. Catechin alone had no antifungal activity within the concentration range tested. Its use in combination with miconazole resulted in complete inhibition of growth in the sensitive C. glabrata isolate and a significant growth reduction in the azole resistant C. glabrata clinical isolate. Simultaneous use of catechin and miconazole leads to increased intracellular ROS generation. The enhanced susceptibility of C. glabrata clinical isolates to miconazole by catechin was accompanied with the intracellular accumulation of ROS and changes in the plasma membrane permeability, as measured using fluorescence anisotropy, affecting the function of plasma membrane proteins. [ABSTRACT FROM AUTHOR]

Candida infective endocarditis is a rare but serious entity that often requires aggressive treatment. However, treatment can be challenging in patients infected with drug-resistant fungi and/or with substantial comorbidity. Moreover, recommendations in treatment guidelines for these patients are based on limited clinical data due to their rarity. Here we report a case of Nakaseomyces glabrata (Candida glabrata) prosthetic valve endocarditis in a patient with congenital heart disease. This case illustrates a therapeutic dilemma for Nakaseomyces glabrata prosthetic valve endocarditis and the need for novel antifungal drugs and further clinical studies.

Background: Conventional antifungals used to treat fungal infections are no longer as effective, leading to increased mortality. On the other hand, there is an emergence of multidrug-resistant (MDR) fungal strains and for this reason, finding new treatments or substances that have an antifungal effect is noticeable. Therefore, this study aimed to determine the antifungal effects of extracts of Arnebia euchroma on the growth of Candida species isolated from patients with COVID-19-associated oral candidiasis. Materials and Methods: In the present experimental study, watery and alcoholic extracts of Arnebia euchroma were prepared by the maceration method. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of alcoholic and watery extract of Arnebia euchroma were evaluated against clinical and standard isolates of Candida albicans, Candida glabrata, Candida tropicalis, Candida parapsilosis, and Candida krusei clinical isolates according to the Clinical and Laboratory Standards Institute document M27-A3 (CLSI M27-A3) broth microdilution protocol. Results: The results of the present study showed that all the investigated isolates were sensitive to watery and alcoholic extracts of Arnebia euchroma. The MIC and MFC of Arnebia euchroma watery extract for Candida albicans were 512 µg/mL and for Candida glabrata were 1024 µg/m, as well as the MIC and MFC of this extract for Candida tropicalis, Candida parapsilosis, and Candida krusei were 2048 µg/mL. Whereas the MIC and MFC of the Arnebia euchroma alcoholic extract for Candida albicans were 0.015625 µg/mL and for Candida glabrata were 256 µg/mL, also the MIC and MFC of this extract for Candida tropicalis and Candida parapsilosis were 512 µg/mL and for Candida krusei were 1024 µg/mL. Conclusion: All the studied Candida isolates were sensitive to both types of Arnebia euchroma root extract, and the alcoholic extract, compared with the watery extract, inhibited the growth of the tested Candida isolates at a lower concentration.

Background and Purpose: The COVID-19 pandemic may be an aggravating risk factor for the delay of the diagnoses of serious illnesses, such as oral squamous cell carcinoma, as well as poor management of patients with underlying morbidities, the onset of oral lesions, and antifungal susceptibility to opportunistic fungal infections. Oral candidiasis is one of the most common oral features of COVID-19.Case Report: This study aimed to report an 83-year-old female diagnosed with oral carcinoma who developed oropharyngeal candidiasis after falling ill with COVID-19. In late 2020, this patient was hospitalized for COVID-19 pneumonia. A fissured tongue with white scars appeared after the COVID-19 recovery that caused pain, dysphasia, and dysarthria. The sequencing result based on the internal transcribed spacer rDNA region confirmed Candida glabrata. Its antifungal susceptibility showed susceptibility to nystatin, fluconazole, and caspofungin, but resistance to the other azoles and amphotericin B.Conclusion: Risk of fungal infections, such as Candida seems to be high in patients with severe COVID-19, mainly affecting the oral mucosa. However, whether they are directly attributed to COVID-19 or other surrounding factors is unknown.

ABSTRACTCandida auris is an emerging yeast pathogen of major concern because of its ability to cause hospital outbreaks of invasive candidiasis and to develop resistance to antifungal drugs. A majority of C. auris isolates are resistant to fluconazole, an azole drug used for the treatment of invasive candidiasis. Mechanisms of azole resistance are multiple, including mutations in the target gene ERG11 and activation of the transcription factors Tac1b and Mrr1, which control the drug transporters Cdr1 and Mdr1, respectively. We investigated the role of the transcription factor Upc2, which is known to regulate the ergosterol biosynthesis pathway and azole resistance in other Candida spp. Genetic deletion and hyperactivation of Upc2 by epitope tagging in C. auris resulted in drastic increases and decreases in susceptibility to azoles, respectively. This effect was conserved in strains with genetic hyperactivation of Tac1b or Mrr1. Reverse transcription PCR analyses showed that Upc2 regulates ERG11 expression and also activates the Mrr1/Mdr1 pathway. We showed that upregulation of MDR1 by Upc2 could occur independently from Mrr1. The impact of UPC2 deletion on MDR1 expression and azole susceptibility in a hyperactive Mrr1 background was stronger than that of MRR1 deletion in a hyperactive Upc2 background. While Upc2 hyperactivation resulted in a significant increase in the expression of TAC1b, CDR1 expression remained unchanged. Taken together, our results showed that Upc2 is crucial for azole resistance in C. auris, via regulation of the ergosterol biosynthesis pathway and activation of the Mrr1/Mdr1 pathway. Notably, Upc2 is a very potent and direct activator of Mdr1.IMPORTANCECandida auris is a yeast of major medical importance causing nosocomial outbreaks of invasive candidiasis. Its ability to develop resistance to antifungal drugs, in particular to azoles (e.g., fluconazole), is concerning. Understanding the mechanisms of azole resistance in C. auris is important and may help in identifying novel antifungal targets. This study shows the key role of the transcription factor Upc2 in azole resistance of C. auris and shows that this effect is mediated via different pathways, including the regulation of ergosterol biosynthesis and also the direct upregulation of the drug transporter Mdr1.

Candida glabrata is an important opportunistic human pathogen well known to develop resistance to antifungal drugs. Due to their numerous desirable qualities, antimicrobial lipopeptides have gained significant attention as promising candidates for antifungal drugs. In the present study, two bioactive lipopeptides (AF4 and AF5 m/z 1071.5 and 1085.5, respectively), coproduced and purified from Bacillus subtilis RLID12.1, consist of seven amino acid residues with lipid moieties. In our previous studies, the reversed phased-HPLC purified lipopeptides demonstrated broad-spectrum of antifungal activities against over 110 Candida albicans, Candida non-albicans and mycelial fungi. Two lipopeptides triggered membrane permeabilization of C. glabrata cells, as confirmed by propidium iodide-based flow cytometry, with PI uptake up to 99% demonstrating fungicidal effects. Metabolic inactivation in treated cells was confirmed by FUN-1-based confocal microscopy. Together, the results indicate that these lipopeptides have potentials to be developed into a new set of antifungals for combating fungal infections.

In the study, it was aimed to develop new candidate inhibitor molecules by targeting the AWP1 protein structure of Candida glabrata organism. Hesperetin molecule was taken as a reference and different substituted groups were attached to the determined ends of the molecule to increase the inhibition potential on the protein structure. A total of 100 molecules were designed and after conformer distribution using the Molecular Mechanics/MMFF method for each designed molecule, the area, volume, weight, energy, EHOMO, ELUMO, polarizability, dipole moment, log P values of these molecules were calculated using the Semi Empirical/PM6 method. Molecular docking studies of the optimized molecules were carried out through the Autodock Vina program. After the docking studies, the interactions of the designed molecules with the active site amino acids of the protein structure were analyzed by BIOVIA Discovery Studio Client software in case of possible mutation. As a result of the analysis, five molecules with higher binding energies than other designed molecules and currently used antifungal drugs were recommended.

ABSTRACTThe World Health Organization recently published the first list of priority fungal pathogens highlighting multiple Candida species, including Candida glabrata, Candida albicans, and Candida auris. However, prior studies in these pathogens have been mainly limited to the use of two drug resistance cassettes, NatMX and HphMX, limiting genetic manipulation capabilities in prototrophic laboratory strains and clinical isolates. In this study, we expanded the toolkit for C. glabrata, C. auris, and C. albicans to include KanMX and BleMX when coupled with an in vitro assembled CRISPR-Cas9 ribonucleoprotein (RNP)-based system. Repurposing these drug resistance cassettes for Candida, we were able to make single gene deletions, sequential and simultaneous double gene deletions, epitope tags, and rescue constructs. We applied these drug resistance cassettes to interrogate the ergosterol pathway, a critical pathway for both the azole and polyene antifungal drug classes. Using our approach, we determined for the first time that the deletion of ERG3 in C. glabrata, C. auris, and C. albicans prototrophic strains results in azole drug resistance, which further supports the conservation of the Erg3-dependent toxic sterol model. Furthermore, we show that an ERG5 deletion in C. glabrata is azole susceptible at subinhibitory concentrations, suggesting that Erg5 could act as an azole buffer for Erg11. Finally, we identified a synthetic growth defect when both ERG3 and ERG5 are deleted in C. glabrata, which suggests the possibility of another toxic sterol impacting growth. Overall, we have expanded the genetic tools available to interrogate complex pathways in prototrophic strains and clinical isolates.IMPORTANCEThe increasing problem of drug resistance and emerging pathogens is an urgent global health problem that necessitates the development and expansion of tools for studying fungal drug resistance and pathogenesis. Prior studies in Candida glabrata, Candida auris, and Candida albicans have been mainly limited to the use of NatMX/SAT1 and HphMX/CaHyg for genetic manipulation in prototrophic strains and clinical isolates. In this study, we demonstrated that NatMX/SAT1, HphMX, KanMX, and/or BleMX drug resistance cassettes when coupled with a CRISPR-ribonucleoprotein (RNP)-based system can be efficiently utilized for deleting or modifying genes in the ergosterol pathway of C. glabrata, C. auris, and C. albicans. Moreover, the utility of these tools has provided new insights into ERG genes and their relationship to azole resistance in Candida. Overall, we have expanded the toolkit for Candida pathogens to increase the versatility of genetically modifying complex pathways involved in drug resistance and pathogenesis.

ABSTRACTFluconazole is one of the most commonly used antifungals today. A result of this has been the inevitable selection of fluconazole-resistant organisms. This is an especially acute problem in the pathogenic yeast Candida glabrata. Elevated minimal inhibitory concentrations for fluconazole in C. glabrata are frequently associated with substitution mutations within the Zn2Cys6 zinc cluster-containing transcription factor-encoding gene PDR1. These mutant Pdr1 regulators drive constitutively high expression of target genes like CDR1 that encodes an ATP-binding cassette transporter thought to act as a drug efflux pump. Exposure of C. glabrata to fluconazole induced expression of both Pdr1 and CDR1, although little is known of the molecular basis underlying the upstream signals that trigger Pdr1 activation. Here, we show that the protein phosphatase calcineurin is required for fluconazole-dependent induction of Pdr1 transcriptional regulation. Calcineurin catalytic activity is required for normal Pdr1 regulation, and a hyperactive form of this phosphatase can decrease susceptibility to the echinocandin caspofungin but does not show a similar change for fluconazole susceptibility. Loss of calcineurin from strains expressing two different gain-of-function forms of Pdr1 also caused a decrease in CDR1 expression and increased fluconazole susceptibility, demonstrating that even these hyperactive Pdr1 regulatory mutants cannot bypass the requirement for calcineurin. Our data implicate calcineurin activity as a link tying azole and echinocandin susceptibility together via the control of transcription factor activity.IMPORTANCEDrug-resistant microorganisms are a problem in the treatment of all infectious diseases; this is an especially acute problem with fungi due to the existence of only three major classes of antifungal drugs, including the azole drug fluconazole. In the pathogenic yeast Candida glabrata, mutant forms of a transcription factor called Pdr1 are commonly associated with decreased fluconazole susceptibility and poor clinical outcomes. Here, we identify a protein phosphatase called calcineurin that is required for fluconazole-dependent induction of Pdr1 transcriptional activation and associated drug susceptibility. Gain-of-function mutant forms of Pdr1 still required the presence of calcineurin to confer normally decreased fluconazole susceptibility. Previous studies showed that calcineurin controls susceptibility to the echinocandin class of antifungal drugs, and our data demonstrate that this protein phosphatase is also required for normal azole drug susceptibility. Calcineurin plays a central role in susceptibility to two of the three major classes of antifungal drugs in C. glabrata.

The mechanisms by which Candida glabrata resists host defense peptides and caspofungin are incompletely understood. To identify transcriptional regulators that enable C. glabrata to withstand these classes of stressors, a library of 215 C. glabrata transcriptional regulatory deletion mutants was screened for susceptibility to both protamine and caspofungin. We identified eight mutants that had increased susceptibility to both host defense peptides and caspofungin. Of these mutants, six were deleted for genes that were predicted to specify proteins involved in histone modification. These genes were ADA2, GCN5, SPT8, HOS2, RPD3, and SPP1 Deletion of ADA2, GCN5, and RPD3 also increased susceptibility to mammalian host defense peptides. The Δada2 and Δgcn5 mutants had increased susceptibility to other stressors, such as H2O2 and SDS. In the Galleria mellonella model of disseminated infection, the Δada2 and Δgcn5 mutants had attenuated virulence, whereas in neutropenic mice, the virulence of the Δada2 and Δrpd3 mutants was decreased. Thus, histone modification plays a central role in enabling C. glabrata to survive host defense peptides and caspofungin, and Ada2 and Rpd3 are essential for the maximal virulence of this organism during disseminated infection.

Background: Candida glabrata is an important cause of invasive candidiasis. Echinocandins are the first-line treatment of invasive candidiasis caused by C. glabrata. The epidemiological echinocandin sensitivity requires long-term surveillance and the understanding about whole genome characteristics of echinocandin non-susceptible isolates was limited. Results: The present study investigated the echinocandin susceptibility of 1650 C. glabrata clinical isolates in China from August 2014 to July 2019. The in vitro activity of micafungin was significantly better than those of caspofungin and anidulafungin (P < 0.001), assessed by MIC50/90 values. Whole genome sequencing was conducted on non-susceptible isolates and geography-matched susceptible isolates. Thirteen isolates (0.79%) were resistant to at least one echinocandin. Six isolates (0.36%) were solely intermediate to caspofungin. Common evolutionary analysis of echinocandin-resistant and echinocandin-intermediate isolates revealed genes related with reduced caspofungin sensitivity, including previously identified sphinganine hydroxylase encoding gene SUR2. Genome-wide association study identified SNPs at subtelometric regions that were associated with echinocandin non-susceptibility. In-host evolution of echinocandin resistance of serial isolates revealed an enrichment for non-synonymous mutations in adhesins genes and loss of subtelometric regions containing adhesin genes. Conclusions: The echinocandins are highly active against C. glabrata in China with a resistant rate of 0.79%. Echinocandin non-susceptible isolates carried common evolved genes which are related with reduced caspofungin sensitivity. In-host evolution of C. glabrata accompanied intensive changing of adhesins profile. [ABSTRACT FROM AUTHOR]

Objectives: Dimethyl sulfoxide (DMSO), acetone, ethanol, and methanol are organic solvents commonly used for dissolving drugs in antimicrobial susceptibility testing. However, these solvents have certain antimicrobial activity. Currently, standardized criteria for the selection and dosage of drug solvents in drug susceptibility testing research are lacking. The study aims to provide experimental evidence for the selection and addition limit of drug solvents for the in vitro antifungal susceptibility test of Candida glabrata (C. glabrata). Methods: According to the recommendation of the Clinical and Laboratory Standards Institute (CLSI) M27-A3, a 0.5 McFarland C. glabrata suspension was prepared and then diluted 1:1,000. Next, a gradient dilution method was used to prepare 20%, 10%, 5%, and 2.5% DMSO/acetone/ethanol/methanol. The mixture was plated onto a 96-well plate and incubated at a constant temperature of 35 ℃ for 48 h. The inhibitory effects of DMSO, acetone, ethanol, and methanol on C. glabrata growth and proliferation were analyzed by measuring optical density values at 600 nm (OD600 values). Results: After 48 h incubation, the OD600 values of C. glabrata decreased to different extents in the presence of the four common organic solvents. The decrease in the OD600 values was greater with increasing concentrations within the experimental concentration range. When DMSO and acetone concentrations were higher than 2.5% (containing 2.5%) and methanol and ethanol concentrations were higher than 5.0% (containing 5.0%), the differences were statistically significant compared with the growth control wells without any organic solvent (P < 0.05). Conclusion: All four organic solvents could inhibit C. glabrata growth and proliferation. When used as solvents for drug sensitivity testing in C. glabrata, the concentrations of DMSO, acetone, ethanol, and methanol should be below 2.5%, 2.5%, 5%, and 5%, respectively. [ABSTRACT FROM AUTHOR]

The study describes the synthesis of zinc oxide (ZnO) nanoparticles using Anacardium occidentale cashew apple juice. The synthesized ZnO nanoparticles were characterized by UV–vis spectroscopy, FTIR spectroscopy, X-ray diffraction spectroscopy, and scanning electron microscopy. The unsophisticated observation revealed bio-reduction of Zn2+ by dark reddish Zn0 formation that settled down. The dark reddish precipitate was turned into white precipitates of ZnO nanoparticles while treated with NaOH. UV–visible spectroscopy represented the formation of ZnO nanoparticles, with an absorption band optimized at 284 nm. FTIR analysis shows the functional groups of biomolecules (protein, carbohydrate, and polyphenol) and their bio-reduction and capping processes. XRD analysis confirms the nanoparticles are highly crystalline, with poly-crystalline zinc oxides and hexagonal wurtzite types. SEM analyses revealed the flower shape of the ZnO nanoparticle's size ranges from 106.7 to 169.2 nm. The anticandidal and antibiofilm activity of ZnO nanoparticles against fluconazole-resistant clinical isolates of C. glabrata were evaluated. The ZnO nanoparticle revealed strong anticandidal activity against C. glabrata with an MIC of 48 µg/mL. The sub-MIC doses (4, 8, and 16 µg/mL) of ZnO nanoparticles showed significant antibiofilm activity against fluconazole-resistant clinical isolates of C. glabrata, with maximum biofilm reduction obtained at 16 µg/mL. Thus, the present study concludes that ZnO nanoparticles are a potential agent for the prevention of C. glabrata biofilm, especially the biofilm formed surface of a prosthetic device. [ABSTRACT FROM AUTHOR]

Background: Candida glabrata which belongs to normal microbiota, has caused significant concern worldwide due to its high prevalence and drug resistance in recent years. C. glabrata has developed many strategies to evade the clearance of the host immune system, thereby causing persistent infection. Although coping with the induced DNA damage is widely acknowledged to be important, the underlying mechanisms remain unclear. Results: The present study provides hitherto undocumented evidence of the importance of the regulatory subunits of CgCK2 (CgCkb1 and CgCkb2) in response to DNA damage. Deletion of CgCKB1 or CgCKB2 enhanced cellular apoptosis and DNA breaks and led to cell cycle delay. In addition, deficiencies in survival upon phagocytosis were observed in Δckb1 and Δckb2 strains. Consistently, disruption of CgCKB1 and CgCKB2 attenuated the virulence of C. glabrata in mouse models of invasive candidiasis. Furthermore, global transcriptional profiling analysis revealed that CgCkb1 and CgCkb2 participate in cell cycle resumption and genomic stability. Conclusions: Overall, our findings suggest that the response to DNA damage stress is crucial for C. glabrata to survive in macrophages, leading to full virulence in vivo. The significance of this work lies in providing a better understanding of pathogenicity in C. glabrata-related candidiasis and expanding ideas for clinical therapies. [ABSTRACT FROM AUTHOR]

Introduction: The incidence of candidiasis can vary across various subsites within the head and neck region and is associated with various co-morbidities and risk factors. The increase in the incidence of resistant Non-albicans Candida (NAC) species among these patients and the limited number of available antifungal agents make treatment difficult. A better understanding of the subsite-specific prevalence of candidiasis and its antifungal susceptibility is crucial in enhancing effective control and treatment. Aim: To determine the subsite-specific prevalence of candidiasis among Head and Neck Cancer (HNC) patients undergoing radiotherapy. Materials and Methods: A cross-sectional study was conducted on patients undergoing therapy for head and neck malignancies at the Department of Radiation Oncology, Amala Institute of Medical Sciences, Thrissur, Kerala, India over a four-year period (January 2019 to December 2022). A total of 276 patients aged 18 to 85 years with squamous cell carcinoma were included. Oral samples were collected from patients who developed candidiasis, and co-morbidities and risk factors were documented. Candida species were isolated and identified. Antifungal susceptibility was determined using the VITEK system, and fluconazole susceptibility was compared with the standard disc diffusion method. Data were entered into an Excel sheet and analysed using Statistical Package for the Social Sciences (SPSS) software. Results: Pharynx was the most frequent site of head and neck malignancy, accounting for 104 cases (37.7%), followed by the oral cavity with 83 cases (30.1%). Among patients with malignancies in the pharyngeal region, a high rate of Candida infection was observed in 42 (43.3%) out of 97 cases. Candida species isolated included C. albicans (56, 57.7%), C. tropicalis (26, 26.8%), C. krusei (8, 8.3%), C. glabrata (3, 3.1%), and C. parapsilosis (4, 4.1%). Sixty-five patients (23.5%) had diabetes, which was statistically significant (p-value <0.05). All C. albicans strains were sensitive to fluconazole. The Minimum Inhibitory Concentration (MIC) of voriconazole was very low for all tested Candida species. Conclusion: Patients with pharyngeal and oral cavity carcinomas are at an increased risk of developing candidiasis during radiotherapy. Diabetes is significantly associated with candidiasis. While C. albicans was the most common species isolated, a significant number of NAC species were also identified. Voriconazole exhibited low MIC values for C. krusei and C. glabrata, suggesting its potential as an alternative treatment option. Obtaining VITEK system identification and susceptibility reports is advisable for borderline values that may not be evident using conventional disc diffusion methods. [ABSTRACT FROM AUTHOR]

An unprecedented expansion of antifungal therapy failure incidences in healthcare settings of Candida glabrata is the matter of global concern that needs to be addressed efficiently and effectively. In this pursuit, the present study has investigated the antifungal mechanism of benzylisoquinoline alkaloid berberine using biochemical, metabolic, and gene expression analysis, with the aim to delineate its therapeutic activity against C. glabrata and differentially fluconazole-responsive clinical isolates. Interestingly, the clinical isolates were found to be highly susceptible to berberine. Berberine was found to control the surface properties like hydrophobicity and charge of the cells. The cell membrane composition was altered by berberine, where the ergosterol and fatty acids were affected. The efflux pump activity was inhibited, and osmotic stress was generated in C. glabrata cells upon berberine exposure. The berberine has also generated oxidative stress and activated antioxidant system in C. glabrata cells. Furthermore, these observations were supported by the transcriptional expression study of C. glabrata cell genes (CDR1, RLM1, SLT2, SUR4, KRE1) and metabolomics analysis. Based on fold change analysis, the study identified 20 differential metabolites upon berberine treatment, which belong to central carbon, amino acids, and nucleotide pathways. The checkerboard analysis revealed the potentiation of some classically used antifungal drugs by berberine, thus suggesting it as a combinatorial nutraceutical adjuvant for the eradication of fungal infections. Key points: • Berberine exhibited better potency against azole-resistant clinical isolates • Berberine modulated metabolites of different pathways • Berberine generated oxidative stress and blocked efflux pump activity [ABSTRACT FROM AUTHOR]

Candidiasis is one of the most important fungal diseases and generally refers to diseases of the skin or mucosal tissues caused by Candida species. Candida glabrata is an opportunistic human fungal pathogen. Infection with C. glabrata has significantly increased due to innate antifungal drug tolerance and the ability to adhere to mucocutaneous surfaces. Spt-Ada-Gcn5 acetyltransferase complex contains two different post-translational modifications, histone acetylation (HAT) module and deubiquitination (DUB) module, which are decisive in gene regulation and highly conserved in eukaryotes. Previous research in our laboratory found that the HAT module ADA2 could regulate C. glabrata oxidative stress tolerance, drug tolerance, cell wall integrity, and virulence. However, the roles of the DUB module that is comprised of UBP8, SGF11, SGF73 , and SUS1 genes in those phenotypes are not yet understood. In this study, we found that DUB module genes UBP8, SGF11 , and SUS1 , but not SGF73 positively regulate histone H2B DUB. Furthermore, ubp8, sgf11 , and sus1 mutants exhibited decreased biofilm formation and sensitivity to cell wall-perturbing agent sodium dodecyl sulfate and antifungal drug amphotericin B. In addition, the sgf73 mutant showed increased biofilm formation but was susceptible to oxidative stresses, antifungal drugs, and cell wall perturbing agents. The ubp8, sgf11 , and sus1 mutants showed marginal hypovirulence, whereas the sgf73 mutant exhibited virulence similar to the wild type in a murine systemic infection model. In conclusion, the C. glabrata DUB module plays distinct roles in H2B ubiquitination, oxidative stress response, biofilm formation, cell wall integrity, and drug tolerance, but exhibits minor roles in virulence. [ABSTRACT FROM AUTHOR]

Invasive fungal infections caused by Candida spp. are associated with a high mortality rate, particularly in intensive care units (ICU). Only half of the infections are detected while the patient is alive, rendering it one of the most frequently overlooked infections in intensive care units. Candida albicans is the most common infectious agent of candidemia, although the number of other species with various drug resistance profiles is on the increase. In the case presented here, a 73-year-old patient was admitted to the Intensive Care Unit due to multiple organ failure resulting from iatrogenic biliary tract injury. Candida glabrata strain growth was obtained from blood cultures from the central catheter, dialysis catheter and arterial blood. Furthermore, C. glabrata was also obtained from wounds and intraoperative material. The therapy involved micafungin at a dose of 100 mg. [ABSTRACT FROM AUTHOR]

One of the medically important opportunistic fungal pathogen for humans is Candida glabrata that causes various types of candidiasis. Its environmental adaptations and antimicrobial resistance is now a great concern for public health. In the present study, the green tea phytocompounds; EGCg, Chlorogenic acid, Coumaroyl quinic acid and Rutin trihydrate along with a known antimycotic Fluconazole were studied for their antimycotic activity against Candida glabrata. The MIC90 for C. glabrata was observed at 125µg/ml for EGC g, 250 µg/mlf or Chlorogenic acid, 500µg/ml for Coumaroyl quinic acid and Rutin trihydrate while 12.5µg/ml for Fluconazole in macro dilution assay while the MFC values were 1000 µg/ml for EGC g, 500 µg/ml for Chlorogenic acid, Coumaroyl quinic acid, Rutin trihydrate and 50 µg/ml for Fluconazole. In microdilution assay, the MIC90 for C. glabrata was observed 125µg/ml for EGC g and chlorogenic acid, 500µg/ml for Coumaroyl quinic acid, Rutin trihydrate and 12.5µg/ml for Fluconazole while the MFC values were 31.25 µg/ml for Fluconazole, 250 µg/ml for chlorogenic acid and 500 µg/ml for EGC g, Coumaroyl quinic acid and Rutin trihydrate. EGCg and Chlorogenic acid was found to be more effective against C. glabrata and therefore these two were used for synergistic study along with Fluconazole. The viability of HeLa cells (in per cent) was observed ≥100% green tea phyto compounds. The viability of treated cells (in per cent) with a combination of Green tea, phytocompounds and fluconazole was observed between ≥98± 0.79 to ≥ 98± 0.87. Green tea phytocompounds mainly EGC g and chlorogenic acid can be used as synergistic molecules having antimycotic activity against C. glabrata. [ABSTRACT FROM AUTHOR]

Abstract Background Saccharomyces cerevisiae is ubiquitous in the gastrointestinal tract and known as brewer's or baker's yeast. We experienced a case of S. cerevisiae and Candida glabrata co-infectious bloodstream infection. It is rare to detect both S. cerevisiae and Candida species in blood cultures together. Case We treated a 73-year-old man who developed a pancreaticoduodenal fistula infection after pancreaticoduodenectomy. The patient had a fever on postoperative day 59. We took blood cultures and detected C. glabrata. Thus, we started micafungin. On postoperative day 62, we retested blood cultures, and detected S cerevisiae and C. glabrata. We changed micafungin to liposomal amphotericin B. Blood cultures became negative on postoperative day 68. We changed liposomal amphotericin B to fosfluconazole and micafungin because of hypokalemia. He got well, and we terminated antifungal drugs 18 days after the blood cultures became negative. Conclusion Co-infection with S. cerevisiae and Candida species is rare. In addition, in this case, S. cerevisiae developed from blood cultures during micafungin administration. Thus, micafungin may not be effective enough to treat S. cerevisiae fungemia, although echinocandin is considered one of the alternative therapy for Saccharomyces infections.

Abstract Background As highly-conserved types of lipid flippases among fungi, P4-ATPases play a significant role in various cellular processes. Cdc50 acts as the regulatory subunit of flippases, forming heterodimers with Drs2 to translocate aminophospholipids. Cdc50 homologs have been reported to be implicated in protein trafficking, drug susceptibility, and virulence in Saccharomyces cerevisiae, Candida albicans and Cryptococcus neoformans. It is likely that Cdc50 has an extensive influence on fungal cellular processes. The present study aimed to determine the function of Cdc50 in Candida glabrata by constructing a Δcdc50 null mutant and its complemented strain. Results In Candida glabrata, the loss of Cdc50 led to difficulty in yeast budding, probably caused by actin depolarization. The Δcdc50 mutant also showed hypersensitivity to azoles, caspofungin, and cell wall stressors. Further experiments indicated hyperactivation of the cell wall integrity pathway in the Δcdc50 mutant, which elevated the major cell wall contents. An increase in exposure of β-(1,3)-glucan and chitin on the cell surface was also observed through flow cytometry. Interestingly, we observed a decrease in the phagocytosis rate when the Δcdc50 mutant was co-incubated with THP-1 macrophages. The Δcdc50 mutant also exhibited weakened virulence in nematode survival tests. Conclusion The results suggested that the lipid flippase subunit Cdc50 is implicated in yeast budding and cell wall integrity in C. glabrata, and thus have a broad influence on drug susceptibility and virulence. This work highlights the importance of lipid flippase, and offers potential targets for new drug research.

Candida albicans and Candida glabrata are two common opportunistic fungi that can be co-isolated in oropharyngeal candidiasis (OPC). Hypha is a hallmark of the biofilm formation of C. albicans, indispensable for the attachment of C. glabrata, which is seldom in mycelial morphology. Increasing evidence reveals a hypoxic microenvironment in interior fungal biofilms, reminding of a fact that inflammation is usually accompanied by oxygen deprivation. As a result, it is assumed that the disaggregation of hypha-mediated hypoxia of biofilms might be a solution to alleviate OPC. Based on this hypothesis, sodium houttuyfonate (SH), a well-identified traditional herbal compound with antifungal activity, is used in combination with fluconazole (FLU), a well-informed synthesized antimycotics, to investigate their impact on filamentation in C. albicans and C. glabrata dual biofilms and the underlying mechanism of their combined treatment on OPC. The results show that compared with the single therapy, SH plus FLU can inhibit the hyphal growth in the mixed biofilms in vitro, decrease the fungal burden of oral tissues and internal organs, restore mucosal epithelial integrity and function, and reduce hypoxic microenvironment and inflammation in a mice OPC model. The possible mechanism of the combined therapy of SH plus FLU can be attributed to the regulation of HIF-1α/IL-17A axis through direct abrogation of the dual Candida biofilm formation. This study highlights the role of HIF-1α/IL-17A axis and the promising application of SH as a sensitizer of conventional antifungals in the treatment of OPC.

Candida species are the most commonly isolated opportunistic fungal pathogens in humans. Candida albicans causes most of the diagnosed infections, closely followed by Candida glabrata. C. albicans is well studied, and many genes have been shown to be important for infection and colonization of the host. It is however less clear how C. glabrata infects the host. With the help of fungal RNA enrichment, we here investigated for the first time the transcriptomic profile of C. glabrata during urinary tract infection (UTI) in mice. In the UTI model, bladders and kidneys are major target organs and therefore fungal transcriptomes were addressed in these organs. Our results showed that, next to adhesins and proteases, nitrogen metabolism and regulation play a vital role during C. glabrata UTI. Genes involved in nitrogen metabolism were upregulated and among them we show that DUR1,2 (urea amidolyase) and GAP1 (amino acid permease) were important for virulence. Furthermore, we confirmed the importance of the glyoxylate cycle in the host and identified MLS1 (malate synthase) as an important gene necessary for C. glabrata virulence. In conclusion, our study shows with the support of in vivo transcriptomics how C. glabrata adapts to host conditions.

Candida glabrata is believed to be the underlying cause of many human ailments, including oral, gastrointestinal, and vaginal disorders. C. glabrata-caused deep-seated infections, coupled with its resistance to antifungal drugs, may contribute to a high mortality rate. Resveratrol is a polyphenol and can achieve better therapeutic effects when administered in combination with micafungin, but the underlying molecular mechanisms remain unknown. Here, we investigate the effects of varying doses of resveratrol on the proliferation, apoptosis, and activity of macrophages, which were co-cultured with micafungin-pretreated C. glabrata. Resveratrol can restore the decreased proliferative activity of macrophages caused by the phagocytosis of C. glabrata. Further investigations demonstrated that this restoration ability exhibited a dose-dependent manner, reaching the highest level at 200 µM of resveratrol. Resveratrol tended to be more effective in inhibiting macrophage apoptosis and reducing reactive oxygen species (ROS) levels with concentration increases. In addition, at medium concentrations, resveratrol may down-regulate the expression of most inflammatory cytokines, whereas at high concentrations, it started to exert pro-inflammatory functions by up-regulating their expressions. Macrophages may shift from an anti-inflammatory (M2) phenotype to an inflammatory (M1) phenotype by resveratrol at 200 µM, and from M1 to M2 at 400 µM. Our research shows that resveratrol with micafungin are effective in treating C. glabrata infections. The resveratrol-micafungin combination can reduce the production of ROS, and promote the proliferation, inhibit the apoptosis, and activate the polarization of macrophages in a dose-dependent manner. This study offers insights into how this combination works and may provide possible direction for further clinical application of the combination.

The prevalence of invasive candidiasis caused by non-Candida albicans has rapidly increased. Candida glabrata (Nakaseomyces glabrata) is an important pathogen associated with substantial mortality. Our study examined the antifungal temporal susceptibility of C. glabrata and cross-resistance/non-wild-type patterns with other azoles and echinocandins. Laboratory data of all adult patients with C. glabrata isolated from clinical specimens at the Mayo Clinic, Rochester, from 2012 to 2022 were collected. Clinical and Laboratory Standards Institute (CLSI) and European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints were used. We obtained 1046 C. glabrata isolates from 877 patients. Using CLSI and EUCAST breakpoints, 187 (17.9%) isolates and 256 (24.5%) isolates were fluconazole-resistant, respectively. Focusing on C. glabrata bloodstream infections, fluconazole-resistance ranged from 16 to 22%. Among those 187 fluconazole-resistant isolates, 187 (100%) and 184 (98.4%) isolates were also voriconazole and posaconazole non-wild-type, respectively, with 97 (51.9%) isolates deemed non-wild type for itraconazole. The fluconazole susceptibility pattern has not changed over the past decade. The proportion of fluconazole-resistant C. glabrata is relatively high, which could be due to the complexity of patients and fluconazole exposure. Itraconazole appears to be a compelling step-down therapy for fluconazole-resistant C. glabrata, given the high proportion of wild-type isolates. Further research to examine clinical outcomes is warranted. [ABSTRACT FROM AUTHOR]

SGLT (sodium-glucose cotransporter) 2 inhibitors enhance urinary glucose excretion by inhibiting glucose reabsorption in the proximal renal tubule. In Japan, it has been administered for diabetes since 2014. Recently, the indication has been expanded to include chronic heart failure and chronic renal failure, and the number of prescriptions will be expected to increase in the future. Although urinary tract and genital tract infections are listed as adverse events of SGLT2 inhibitors, the discontinuation criteria of the drug and optimal follow-up methods are not still clear. Consequently, these are unmet needs within this field. We herein report a case of fungal infection which occurred while the patient was taking a SGLT2 inhibitor. A 77-year-old male with type 2 diabetes mellitus was admitted to our hospital in August 20XX complaining of fever and immobility. On the basis of further examination, he was diagnosed with acute pyelonephritis and underwent antibacterial therapy. Ipragliflozin, an SGLT2 inhibitor, was changed to insulin on admission day. Since Candida glabrata was detected in urine and blood cultures on the fifth day, antifungal therapy was added as antibacterial management. He was introduced to the ophthalmology department due to fungemia, and was diagnosed with fungal endophthalmitis. Due to an improvement of intraocular findings, the patient was discharged on the 42nd day after admission. Because urinary tract infections and genital infections such as necrotizing fasciitis (Fournier's gangrene) have been reported to be associated with SGLT2 inhibitors, urologists need to keep in mind the urological risks of SGLT2 inhibitors. [ABSTRACT FROM AUTHOR]

Essential oils are a complex mixture of aromatic substances whose pharmacological actions, including antimicrobial, antioxidant, anticancer, and anti-inflammatory activities, have been widely reported. This study aimed to evaluate the anti-Candida and dermal anti-inflammatory activity of essential oils from native and cultivated Ecuadorian plants. Essential oils from Bursera graveolens, Dacryodes peruviana, Mespilodaphne quixos, and Melaleuca armillaris were isolated by hydrodistillation and were characterized physically and chemically. Its tolerance was analyzed by in vitro and in vivo studies. The antifungal activity was studied against Candida albicans, Candida glabrata, and Candida parapsilosis, whereas the anti-inflammatory effect was evaluated by a mouse ear edema model. The main compounds were limonene, α-phellandrene, (E)-methyl cinnamate, and 1,8-cineole, respectively. All essential oils showed high tolerability for skin application, antifungal activity against the three Candida strains, and anti-inflammatory efficacy by decreasing edema and overexpression of pro-inflammatory cytokines. Dacryodes peruviana essential oil showed the highest antifungal activity. On the other hand, Dacryodes peruviana and Melaleuca armillaris showed the greatest anti-inflammatory potential, decreasing edema by 53.3% and 65.25%, respectively, and inhibiting the overexpression of TNF-α, IL-8, IL-17A, and IL-23. The results suggest that these essential oils could be used as alternative therapies in the treatment of both cutaneous candidiasis and dermal inflammation. [ABSTRACT FROM AUTHOR]