Antifungal Susceptibility and Candida sp. Biofilm Production in Clinical Isolates of HIV-Positive Brazilian Patients under HAART Therapy.

The aim of the present study was to characterize biofilms formed by Candida spp. clinical isolates (n = 19), isolated from the oral mucosa of HIV-positive patients. For characterizing the biofilms formed by several Candida sp. strains, isolated from HIV-positive patients, in terms of formed biomass, matrix composition and antifungal susceptibility profile, clinical isolates (n = 19) were collected from oral mucosa and identified. The biofilm of the samples was cultured with fluconazole (1250 mg/L), voriconazole (800 mg/L), anidulafungin (2 mg/L) or amphotericin B (2 mg/L). Afterwards, the quantification of the total biomass was performed using crystal violet assay, while the proteins and carbohydrates levels were quantified in the matrix. The results showed a predominance of C. albicans, followed by C. krusei. Around 58% of the Candida spp. biofilm had susceptibility to fluconazole and voriconazole (800 mg/L), 53% to anidulafungin and 74% to amphotericin B. C. krusei presented both the lowest and the highest biofilm matrix contents in polysaccharides and proteins. The low resistance to antifungal agents reported here was probably due to the fact that none of the participants had a prolonged exposure to these antifungals. A predominance of less virulent Candida spp. strains with low or no resistance to antifungals was observed. This can be attributed to a low fungal selective pressure. This most probably happened due to a low fungal selective pressure but also due to a good adherence to HAART therapy, which guarantees a stable and stronger immune patient response.

Oral candidiasis in patients with kidney transplantation in Iran: prevalence and antifungal susceptibility pattern.

Aim: This study aimed to identify Candida species recovered from the oral cavity of patients with kidney transplantation. Materials & methods: Two swabs were taken from the oral cavities of 40 patients before and after transplantation, cultured on Sabouraud dextrose agar, and yeasts identified. Antifungal drug susceptibility testing was performed with fluconazole and itraconazole. Results: Candida glabrata was the most frequently isolated species in patients, followed by Candida albicans and Rhodotorula. C. glabrata isolates from patients before transplantation were resistant to fluconazole, whereas C. albicans was fluconazole-resistant both before and after transplantation. Conclusion: The importance of non-albicans Candida species in the oral cavity of patients sheds light on performing antifungal tests for achieving the best outcome to prevent therapeutic failure.

Biomaterials with antifungal strategies to fight oral infections.

Oral fungal infections pose a threat to human health and increase the economic burden of oral diseases by prolonging and complicating treatment. A cost-effective strategy is to try to prevent these infections from happening in the first place. With this purpose, biomaterials with antifungal properties are a crucial element to overcome fungal infections in the oral cavity. In this review, we go through different kinds of biomaterials and coatings that can be used to functionalize them. We also review their potential as a therapeutic approach in addition to prophylaxis, by going through traditional and alternative antifungal compounds, e.g., essential oils, that could be incorporated in them, to enhance their efficacy against fungal pathogens. We aim to highlight the potential of these technologies and propose questions that need to be addressed in prospective research. Finally, we intend to concatenate the key aspects and technologies on the use of biomaterials in oral health, to create an easy to find summary of the current state-of-the-art for researchers in the field.

Characterization of Oral Candida spp. Biofilms in Children and Adults Carriers from Eastern Europe and South America.

BACKGROUND: Candida albicans and non-Candida albicans Candida species (NCACs) are known to colonize and invade various tissues, including the oral mucosa. In this work, we aimed to characterize mature biofilms of several Candida spp. clinical isolates (n = 33) obtained from the oral mucosa of children, adults, and elders of Eastern Europe and South America. METHODS: Each strain was evaluated for its capacity to form biofilms in terms of total biomass using the crystal violet assay and for matrix components production (proteins and carbohydrates) using the BCA and phenol-sulfuric tests, respectively. The effect of different antifungals on biofilm formation was studied. RESULTS: in the children's group, a predominance of C. krusei (81%) was observed, while, among adults, the main species was C. albicans (59%). Most strains showed a reduced response to antimicrobial drugs when in biofilm form (p < 0.01). Moreover, it was observed that strains isolated from children produced more matrix, with higher levels of protein and polysaccharides. CONCLUSIONS: children were more likely to be infected by NCACs than adults. More importantly, these NCACs were able to form biofilms richer in matrix components. This finding is of clinical importance, particularly in pediatric care, since stronger biofilms are highly associated with antimicrobial resistance, recurrent infections, and higher therapeutic failure.

Role of the Dietary Phytochemical Curcumin in Targeting Cancer Cell Signalling Pathways.

The diarylheptanoid curcumin [(1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)hepta-1,6-diene-3,5-dione] is one of the phenolic pigments responsible for the yellow colour of turmeric (Curcuma longa L.). This phytochemical has gained much attention in recent years due to its therapeutic potential in cancer. A range of drug delivery approaches have been developed to optimise the pharmacokinetic profile of curcumin and ensure that it reaches its target sites. Curcumin exhibits numerous biological effects, including anti-inflammatory, cardioprotective, antidiabetic, and anti-aging activities. It has also been extensively studied for its role as a cancer chemopreventive and anticancer agent. This review focusses on the role of curcumin in targeting the cell signalling pathways involved in cancer, particularly via modulation of growth factors, transcription factors, kinases and other enzymes, pro-inflammatory cytokines, and pro-apoptotic and anti-apoptotic proteins. It is hoped that this study will help future work on the potential of curcumin to fight cancer.

Combination of Farnesol with Common Antifungal Drugs: Inhibitory Effect against Candida Species Isolated from Women with RVVC.

Background and Objectives: Vulvovaginal candidiasis (VVC) is a mucous membrane infection, with an increased rate of antifungal resistance of Candida species. In this study, the in vitro efficacy of farnesol alone or in combination with traditional antifungals was assessed against resistant Candida strains recovered from women with VVC. Materials and Methods: Eighty Candida isolates were identified by multiplex polymerase chain reaction (PCR), and the antifungal susceptibility to amphotericin B (AMB), fluconazole (FLU), itraconazole (ITZ), voriconazole (VOR), clotrimazole (CTZ), and farnesol was tested by the standard microdilution method. The combinations of farnesol with each antifungal were calculated based on the fractional inhibitory concentration index (FICI). Result: Candida glabrata was the predominant species (48.75%) isolated from vaginal discharges, followed by C. albicans (43.75%), C. parapsilosis (3.75%), a mixed infection of C. albicans and C. glabrata (2.5%) and C. albicans and C. parapsilosis (1%). C. albicans and C. glabrata isolates had lower susceptibility to FLU (31.4% and 23.0%, respectively) and CTZ (37.1% and 33.3%, respectively). Importantly, there was "synergism" between farnesol-FLU and farnesol-ITZ against C. albicans and C. parapsilosis (FICI = 0.5 and 0.35, respectively), reverting the original azole-resistant profile. Conclusion: These findings indicate that farnesol can revert the resistance profile of azole by enhancing the activity of FLU and ITZ in resistant Candida isolates, which is a clinically promising result.

Thymoquinone Antifungal Activity against Candida glabrata Oral Isolates from Patients in Intensive Care Units-An In Vitro Study.

The number of Candida spp. infections and drug resistance are dramatically increasing worldwide, particularly among immunosuppressed patients, and it is urgent to find novel compounds with antifungal activity. In this work, the antifungal and antibiofilm activity of thymoquinone (TQ), a key bioactive constituent of black cumin seed Nigella sativa L., was evaluated against Candida glabrata, a WHO 'high-priority' pathogen. Then, its effect on the expression of C. glabrata EPA6 and EPA7 genes (related to biofilm adhesion and development, respectively) were analyzed. Swab samples were taken from the oral cavity of 90 hospitalized patients in ICU wards, transferred to sterile falcon tubes, and cultured on Sabouraud Dextrose Agar (SDA) and Chromagar Candida for presumptive identification. Next, a 21-plex PCR was carried out for the confirmation of species level. C. glabrata isolates underwent antifungal drug susceptibility testing against fluconazole (FLZ), itraconazole (ITZ), amphotericin B (AMB), and TQ according to the CLSI microdilution method (M27, A3/S4). Biofilm formation was measured by an MTT assay. EPA6 and EPA7 gene expression was assessed by real-time PCR. From the 90 swab samples, 40 isolates were identified as C. glabrata with the 21-plex PCR. Most isolates were resistant to FLZ (n = 29, 72.5%), whereas 12.5% and 5% were ITZ and AMB resistant, respectively. The minimum inhibitory concentration (MIC50) of TQ against C. glabrata was 50 µg/mL. Importantly, TQ significantly inhibited the biofilm formation of C. glabrata isolates, and EPA6 gene expression was reduced significantly at MIC50 concentration of TQ. TQ seems to have some antifungal, antibiofilm (adhesion) effect on C. glabrata isolates, showing that this plant secondary metabolite is a promising agent to overcome Candida infections, especially oral candidiasis.

Our current clinical understanding of Candida biofilms: where are we two decades on?

Clinically we have been aware of the concept of Candida biofilms for many decades, though perhaps without the formal designation. Just over 20 years ago the subject emerged on the back of progress made from the bacterial biofilms, and academic progress pace has continued to mirror the bacterial biofilm community, albeit at a decreased volume. It is apparent that Candida species have a considerable capacity to colonize surfaces and interfaces and form tenacious biofilm structures, either alone or in mixed species communities. From the oral cavity, to the respiratory and genitourinary tracts, wounds, or in and around a plethora of biomedical devices, the scope of these infections is vast. These are highly tolerant to antifungal therapies that has a measurable impact on clinical management. This review aims to provide a comprehensive overight of our current clinical understanding of where these biofilms cause infections, and we discuss existing and emerging antifungal therapies and strategies.

In Silico Identification of Potential Insect Peptides against Biofilm-Producing Staphylococcus aureus.

Biofilm-producing Staphylococcus aureus (SA) strains are frequently found in medical environments, from surgical/ wound sites, medical devices. These biofilms reduce the efficacy of applied antibiotics during the treatment of several infections, such as cystic fibrosis, endocarditis, or urinary tract infections. Thus, the development of potential therapeutic agents to destroy the extra protective biofilm layers or to inhibit the biofilm-producing enzymes is urgently needed. Advanced and cost-effective bioinformatics tools are advantageous in locating and speeding up the selection of antibiofilm candidates. Based on the potential drug characteristics, we have selected one-hundred thirty-three antibacterial peptides derived from insects to assess for their antibiofilm potency via molecular docking against five putative biofilm formation and regulated target enzymes: the staphylococcal accessory regulator A or SarA (PDB ID: 2FRH), 4,4'-diapophytoene synthase or CrtM (PDB ID: 2ZCQ), clumping factor A or ClfA (PDB ID: 1N67) and serine-aspartate repeat protein C or SdrC (PDB ID: 6LXH) and sortase A or SrtA (PDB ID: 1T2W) of SA bacterium. In this study, molecular docking was performed using HPEPDOCK and HDOCK servers, and molecular interactions were examined using BIOVIA Discovery Studio Visualizer-2019. The docking score (kcal/mol) range of five promising antibiofilm peptides against five targets was recorded as follows: diptericin A (-215.52 to -303.31), defensin (-201.11 to -301.92), imcroporin (-212.08 to -287.64), mucroporin (-228.72 to -286.76), apidaecin II (-203.90 to -280.20). Among these five, imcroporin and mucroporin were 13 % each, while defensin contained only 1 % of positive net charged residues (Arg+Lys) projected through ProtParam and NetWheels tools. Similarly, imcroporin, mucroporin and apidaecin II were 50 %, while defensin carried 21.05 % of hydrophobic residues predicted by the tool PEPTIDE. 2.0. Most of the peptides exhibited potential characteristics to inhibit S. aureus-biofilm formation via disrupting the cell membrane and cytoplasmic integrity. In summary, the proposed hypothesis can be considered a cost-effective platform for selecting the most promising bioactive drug candidates within a limited timeframe with a greater chance of success in experimental and clinical studies.

Microfluidics combined with fluorescence in situ hybridization (FISH) for Candida spp. detection.

One of the most prevalent healthcare-associated infection is the urinary tract infection (UTI), caused by opportunistic pathogens such as Candida albicans or non-albicans Candida species (NACS). Urine culture methods are routinely used for UTI diagnostics due to their specificity, sensitivity and low-cost. However, these methods are also laborious, time- and reagent-consuming. Therefore, diagnostic methods relying on nucleic acids have been suggested as alternatives. Nucleic acid-based methods can provide results within 24 h and can be adapted to point-of-care (POC) detection. Here, we propose to combine fluorescence in situ hybridization (FISH) with a microfluidic platform for the detection of Candida spp. As a case study we used C. tropicalis, which is reported as the second most common NACS urine isolate obtained from patients suspected with UTI. The microfluidic platform proposed in this study relies on hydrodynamic trapping, and uses physical barriers (e.g., microposts) for the separation of target cells from the suspension. Using a specific peptide nucleic acid (PNA) probe, the FISH procedure was applied onto previously trapped C. tropicalis cells present inside the microfluidic platform. Fluorescence signal intensity of hybridized cells was captured directly under the epifluorescence microscope. Overall, the PNA probe successfully detected C. tropicalis in pure culture and artificial urine (AU) using FISH combined with the microfluidic platform. Our findings reveal that FISH using nucleic acid mimics (PNA) in combination with microfluidics is a reliable method for the detection of microorganisms such as C. tropicalis. As such, this work provides the basis for the development of a POC detection platform in the future.

Whole-exome sequencing reveals PSEN1 and ATP7B combined variants as a possible cause of early-onset Lewy body dementia: a case study of genotype-phenotype correlation.

Dementia with Lewy bodies is a neurodegenerative disease, sharing features with Parkinson's and Alzheimer's diseases. We report a case of a patient dementia with Lewy bodies carrying combined PSEN1 and ATP7B mutations. A man developed dementia with Lewy bodies starting at the age of 60 years. CSF biomarkers were of Alzheimer's disease and DaTSCAN was abnormal. Whole-exome sequencing revealed a heterozygous p.Ile408Thr PSEN1 variant and a homozygous p.Arg616Trp ATP7B variant. This case reinstates the need of considering ATP7B mutations when evaluating a patient with parkinsonism and supports p.Ile408Thr as a pathogenic PSEN1 variant.

Overview on the Infections Related to Rare Candida Species.

Atypical Candida spp. infections are rising, mostly due to the increasing numbers of immunocompromised patients. The most common Candida spp. is still Candida albicans; however, in the last decades, there has been an increase in non-Candida albicans Candida species infections (e.g., Candida glabrata, Candida parapsilosis, and Candida tropicalis). Furthermore, in the last 10 years, the reports on uncommon yeasts, such as Candida lusitaniae, Candida intermedia, or Candida norvegensis, have also worryingly increased. This review summarizes the information, mostly related to the last decade, regarding the infections, diagnosis, treatment, and resistance of these uncommon Candida species. In general, there has been an increase in the number of articles associated with the incidence of these species. Additionally, in several cases, there was a suggestive antifungal resistance, particularly with azoles, which is troublesome for therapeutic success.

Marine Compounds with Anti-Candida sp. Activity: A Promised "Land" for New Antifungals.

Candida albicans is still the major yeast causing human fungal infections. Nevertheless, in the last decades, non-Candida albicans Candida species (NCACs) (e.g., Candida glabrata, Candida tropicalis, and Candida parapsilosis) have been increasingly linked to Candida sp. infections, mainly in immunocompromised and hospitalized patients. The escalade of antifungal resistance among Candida sp. demands broadly effective and cost-efficient therapeutic strategies to treat candidiasis. Marine environments have shown to be a rich source of a plethora of natural compounds with substantial antimicrobial bioactivities, even against resistant pathogens, such as Candida sp. This short review intends to briefly summarize the most recent marine compounds that have evidenced anti-Candida sp. activity. Here, we show that the number of compounds discovered in the last years with antifungal activity is growing. These drugs have a good potential to be used for the treatment of candidiasis, but disappointedly the reports have devoted a high focus on C. albicans, neglecting the NCACs, highlighting the need to perform outspreading studies in the near future.

Influence of seasonality on the quality of oysters from the Sado and Mira rivers.

There is a lack of knowledge about the influence of seasonality on the microbial and physicochemical quality of oysters in Sado and Mira rivers. Water, sediment, and oysters (Crassostrea angulata and Crassostrea gigas) were collected for microbiological, nutritional, and sensory analyses. The microbiological water quality and the oyster shell contamination were better during the warmer months. No seasonal effect was observed on sediments and on oyster meat. A good physicochemical and nutritional quality was also observed, with high content of polyunsaturated fatty acids, including omega-3 fatty acids, resulting in good lipid quality indices. From the sensory evaluation, both oysters' species were well scored and presented the highest scores (4) in parameters such as cream-ivory colour, sea smell, firmness and juiciness. These attributes denote the freshness degree at the time of the tasting, reflecting the quality of the bivalve.

Prevalence and Antifungal Susceptibility Profile of Oral Candida spp. Isolates from a Hospital in Slovakia.

Oral fungal infections are a worldwide healthcare problem. Although Candida albicans is still the most common yeast involved in the infections of oral cavity, non-Candida albicans Candida species (NCACs) have been highly related to these infections, particularly in older, immunosuppressed or patients with long exposure to antimicrobial drugs. The goal of this work was to perform a quick epidemiological and mycological study on the oral samples collected from a laboratory of a hospital in Slovakia, for 60 days. The samples' identification was performed by Germ-tube formation test, CHROMID® Candida, Auxacolor 2, ID 32C automated method, and the antifungal susceptibility testing determined by E-test®. Results confirm that comparing with bacteria, yeasts still occur in the lower number, but there is a high rate of antifungal resistance (81.6%)­to, at least one drug­among the collected samples, particularly to azoles and 5'-FC, which is clinically noteworthy.

Enhancing of Wound Healing in Burn Patients through Candida albicans ß-Glucan.

The mortality and disability-adjusted life years (DALYs) of burn patients are decreasing over time. However, finding novel effective treatment approaches using natural agents is highly considered to reduce the burden of burn injuries. One of the recent agents used in wound healing is ß-glucan, mainly extracted from fungi cell walls. This study aimed to evaluate the effect of 5% (m/m) of yeast ß-glucan ointment on burn wound healing and to assess the impact of ß-glucan on cytokines during the treatment. Thirty-three patients with second or third-degree burns were enrolled in this study. Two groups of twenty-three and ten patients used yeast 5% (m/m) ß-glucan ointment (study group) and Stratamed ointment (control), respectively, on a daily basis, for a maximum of four weeks. The size of the burn wounds was measured before and at the end of the treatment. Blood samples of 14 and 10 patients in the ß-glucan and control groups, respectively, were obtained before and after the treatment, and the enzyme-linked immunosorbent assay (ELISA) was performed to measure the serum concentration of the IL-4, IL-17, and IFN-γ cytokines. The log-binomial model was used to assess the efficacy of the ß-glucan ointment on burn wound healing. ANOVA/ANCOVA was employed to assess the effects of ß-glucan on the serum concentration of cytokines. After adjusting for potential confounders/covariates, patients receiving ß-glucan had better wound healing (RR = 4.34; 95% CI: 0.73 to 25.67; p = 0.11). There was a significant difference in IL-4 secretion between the ß-glucan and control groups after adjusting for potential confounders/covariates (MD = 77.27; 95% CI: 44.73 to 109.82; Cohen's d = 2.21; 95% CI: 1.16 to 3.24; p = 0.0001). The results indicate that 5% (m/m) of ß-glucan has efficacy in burn wound healing, and a significant difference was found in the level of IL-4 after receiving ß-glucan. Further studies with a two-arm design and long-term use of ointment are needed to confirm the effect of ß-glucan on wound healing and cytokine secretion.

Rare variants in TP73 in a frontotemporal dementia cohort link this gene with primary progressive aphasia phenotypes.

BACKGROUND AND PURPOSE: TP73 was recently reported to cause amyotrophic lateral sclerosis (ALS). ALS and frontotemporal dementia (FTD) are considered to form part of a continuum. We aimed to investigate whether TP73 variants may be associated with FTD. METHODS: We studied a thoroughly investigated cohort of 65 Portuguese patients with frontotemporal dementia using whole-exome sequencing. The patients had no other known genetic cause for their disease (C9orf72 expansion was also excluded). RESULTS: Of the 65 patients studied, two had rare variants in TP73 (p.Gly605Ser and p.Arg347Trp). Both variants had minor allele frequency <0.001 and were predicted to be pathogenic in silico. The two patients displayed a phenotype that included predominant language impairment, suggestive of non-fluent progressive aphasia. CONCLUSION: We show that two thoroughly studied patients without other known genetic changes harbored TP73 rare variants, which are pathogenic in silico. This adds evidence to support the role of TP73 in the ALS-FTD spectrum, especially in primary progressive aphasia cases.

Application of probiotics in candidiasis management.

Candidiasis (e.g., oral, gastrointestinal, vaginal, urinary tract, systemic) is a worldwide growing problem, since antifungal resistance and immunosuppression states are rising. To address this problem, very few drugs are available for the treatment of Candida spp. infections. Therefore, novel therapeutic strategies are urgently required. Probiotics have been proposed for the prevention and treatment of bacterial infections due to their safety record and efficacy, however, little is still known about their potential role regarding fungal infections. The purpose of this review is to present an updated summary of the evidence of the antifungal effects of probiotics along with a discussion of their potential use as an alternative/complementary therapy against Candida spp. infections. Thus, we performed a literature search using appropriate keywords ("Probiotic + Candida", "Candidiasis treatment", and "Probiotic + candidiasis") to retrieve relevant studies (both preclinical and clinical) with special emphasis on the works published in the last 5 years. An increasing amount of evidence has shown the potential usefulness of probiotics in the management of oral and vulvovaginal candidiasis in recent years. Among other results, we found that, as for bacterial infections, Lactobacillus, Bifidobacterium, and Saccharomyces are the most studied and effective genus for this purpose. However, in other areas, particularly in skincandidiaisis, studies are low or lacking. Thus, further investigation is necessary including in vitro and in vivo studies to establish the usefulness of probiotics in the management of candidiasis.

Biofilm formation in clinically relevant filamentous fungi: a therapeutic challenge.

Biofilms are highly-organized microbial communities attached to a biotic or an abiotic surface, surrounded by an extracellular matrix secreted by the biofilm-forming cells. The majority of fungal pathogens contribute to biofilm formation within tissues or biomedical devices, leading to serious and persistent infections. The clinical significance of biofilms relies on the increased resistance to conventional antifungal therapies and suppression of the host immune system, which leads to invasive and recurrent fungal infections. While different features of yeast biofilms are well-described in the literature, the structural and molecular basis of biofilm formation of clinically related filamentous fungi has not been fully addressed. This review aimed to address biofilm formation in clinically relevant filamentous fungi.

Resveratrol-Based Nanoformulations as an Emerging Therapeutic Strategy for Cancer.

Resveratrol is a polyphenolic stilbene derivative widely present in grapes and red wine. Broadly known for its antioxidant effects, numerous studies have also indicated that it exerts anti-inflammatory and antiaging abilities and a great potential in cancer therapy. Regrettably, the oral administration of resveratrol has pharmacokinetic and physicochemical limitations such as hampering its effects so that effective administration methods are demanding to ensure its efficiency. Thus, the present review explores the published data on the application of resveratrol nanoformulations in cancer therapy, with the use of different types of nanodelivery systems. Mechanisms of action with a potential use in cancer therapy, negative effects, and the influence of resveratrol nanoformulations in different types of cancer are also highlighted. Finally, the toxicological features of nanoresveratrol are also discussed.