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.

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.

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.

A High Rate of Recurrent Vulvovaginal Candidiasis and Therapeutic Failure of Azole Derivatives Among Iranian Women.

Recurrent vulvovaginal candidiasis (RVVC) is one of the most prevalent fungal infections in humans, especially in developing countries; however, it is underestimated and regarded as an easy-to-treat condition. RVVC may be caused by dysbiosis of the microbiome and other host-, pathogen-, and antifungal drug-related factors. Although multiple studies on host-related factors affecting the outcome have been conducted, such studies on Candida-derived factors and their association with RVVC are lacking. Thus, fluconazole-tolerant (FLZT) isolates may cause fluconazole therapeutic failure (FTF), but this concept has not been assessed in the context of Candida-associated vaginitis. Iran is among the countries with the highest burden of RVVC; however, comprehensive studies detailing the clinical and microbiological features of this complication are scarce. Therefore, we conducted a 1-year prospective study with the aim to determine the RVVC burden among women referred to a gynecology hospital in Tehran, the association of the previous exposure to clotrimazole and fluconazole with the emergence of FLZT and fluconazole-resistant (FLZR) Candida isolates, and the relevance of these phenotypes to FTF. The results indicated that about 53% of the patients (43/81) experienced RVVC. Candida albicans and C. glabrata constituted approximately 90% of the yeast isolates (72 patients). Except for one FLZT C. tropicalis isolate, FLZR and FLZT phenotypes were detected exclusively in patients with RVVC; among them, 27.9% (12/43) harbored FLZR strains. C. albicans constituted 81.2% of FLZR (13/16) and 100% of the FLZT (13/13) isolates, respectively, and both phenotypes were likely responsible for FTF, which was also observed among patients with RVVC infected with fluconazole-susceptible isolates. Thus, FTF could be due to host-, drug-, and pathogen-related characteristics. Our study indicates that FLZT and FLZR isolates may arise following the exposure to over-the-counter (OTC) topical azole (clotrimazole) and that both phenotypes can cause FTF. Therefore, the widespread use of OTC azoles can influence fluconazole therapeutic success, highlighting the necessity of controlling the use of weak topical antifungals among Iranian women.

In Vitro Aflatoxin B1 Binding by the Cell Wall and (1→3)-ß-d-Glucan of Baker's Yeast.

The aim of this study was to evaluate the ability of heat-killed baker's yeast (HKBY), the cell wall of baker's yeast (CWBY), and cell wall (1→3)-ß-d-glucan of baker's yeast (BGBY) to bind aflatoxin B1 (AFB1) in phosphate-buffered saline (PBS) spiked with 0.5 µg/mL AFB1. Baker's yeast ( Saccharomyces cerevisiae) was heat killed by autoclaving at 121°C for 10 min. The cell wall was physically extracted, and (1→3)-ß-d-glucan was extracted by a modified method. The concentration of AFB1 was determined by high-performance liquid chromatography after exposure to binders for three contact times, 30 min, 5 h, and 24 h, at room temperature. AFB1 binding by HKBY, CWBY, and BGBY was 6.30 to 46.34%. The lowest binding capacity was found for HKBY with a contact time of 30 min, and the highest binding capacity was found for BGBY with a contact time of 24 h. Among binders, CWBY had the highest binder-AFB1 complex stability during washing with PBS, and the lowest stability was found for HKBY complexes. Results of this study indicated that BGBY was the most effective binder, and more exposure to BGBY removes more AFB1 from PBS.

Lung cancer and ß-glucans: review of potential therapeutic applications.

The potential of natural substances with immunotherapeutic properties has long been studied. ß-glucans, a cell wall component of certain bacteria and fungi, potentiate the immune system against microbes and toxic substances. Moreover, ß-glucans are known to exhibit direct anticancer effects and can suppress cancer proliferation through immunomodulatory pathways. Mortality of lung cancer has been alarmingly increasingly worldwide; therefore, treatment of lung cancer is an urgent necessity. Numerous researchers are now dedicated to using ß-glucans as a therapy for lung cancer. In the present attempt, we have reviewed the studies addressing therapeutic effects of ß-glucans in primary and metastatic lung cancer published in the time period of 1991-2016.

Functionalized nanoscale ß-1,3-glucan to improve Her2+ breast cancer therapy: In vitro and in vivo study.

We fabricated a targeted delivery system for doxorubicin (Dox) using ß-1,3-glucan (Glu) as a carrier and decorated by trastuzumab antibody having the status of targeting agent against Her2+ breast tumors. Glu-Dox conjugates were also functionalized with polyethylenimine (PEI) intended for increasing specific cellular uptake of prepared nanoparticles. The self-assembled nanoparticles were prepared through conjugation of Dox- [Glu-Dox-] using succinic anhydride (Sa) in place of a linker. Nanoparticles had spherical morphology with positive zeta potential. In-vitro cell viability assay on two breast cancer cell lines demonstrated acceptable toxicity against tested cell lines. Confocal microscopic images demonstrated the remarkable cytoplasmic uptake of the nanoparticles in Her2-overexpressing 4T1 cells. A controlled release of Dox from Glu-Dox nanoparticles was investigated. In-vivo studies were performed on female Balb/C mice. The volume of the induced tumors was calculated following intravenous administration of nanoparticles. The tumor volume diminished efficiently and more rapidly after administration of nanoparticles containing Dox. Based on survival results, the formulation of Dox targeted nanoparticles appeared very promising for the treatment of tumors. It could be concluded that Glu-Dox targeted nanoparticles have potential advantages for delivering anticancer drugs to the target tissue.