Antifungal Chemotherapy Research Articles

Clinico-Pathological Study of Invasive Fungal Sinusitis in Ibadan, Nigeria: A Case Series

Background: Invasive fungal sinusitis is one of the less common forms of fungal infection more commonly described in North Africa and Asia. It affects healthy and immunologically competent individuals typically complicating chronic rhinosinusitis. Surgical debridement and adjuvant antifungal treatment are the mainstay of management of this condition. Objective: To describe the clinical presentation, pathological features and management of patients with invasive fungal sinusitis managed at a tertiary health facility, southwestern Nigeria. Method: Medical records of all patients with invasive fungal sinusitis managed between January 2009 and December 2018 were retrospectively reviewed. Results: Six patients with invasive fungal sinusitis were managed during the study period. All patients were immunocompetent and the mean age at presentation was 30.7 years ± 7.2 years. The average duration of symptoms prior to presentation was 18.5 months (Interquartile range, 67.5 months), and all six patients had orbital involvement and intracranial extension of the mass at presentation. They all had surgical debridement, and the specimens were sent for histological examination. Mycological studies carried out on two specimens isolated Aspergillus fumigatusas the fungal agent and all patients were started on post-operative oral antifungal chemotherapy. Five patients completed their chemotherapy and fared well with no recurrence while one patient had irregular and incomplete antifungal treatment, and developed recurrent infection before abandoning further treatment. Conclusion: Chronic invasive fungal sinusitis is an uncommon infection and fairly difficult to manage. However, timely diagnosis and combined surgical and medical treatment can give good outcomes in the patients.

Investigation of oxidative potential of mahasudarshan churna using goat liver as in-vitro experimental model

Antifungal chemotherapy depends on bio-chemical alterations between fungi and mammals. Unlike bacteria, which are prokaryotes, both fungi and mammals are eukaryotes and the biochemical differences between them are not significant. However, there are some differences (in structure & metabolism) and focus is on these differences that act as targets for development of antifungal agents. The current recommendation of standard TB chemotherapy, called Directly observed treatment (DOTS) is a therapy of six month in which consists an first two-month phase of cure with four first-line drugs i.e. isoniazid, Rifampicin, Pyrazinamide, and Ethambutol. In this study large number of compounds is manufactured in which Most of the tested molecules showed maximum bacteriological growth inhibition at tested concentration. The combinations (7e, 7g, 7h, 7i and 7u) exhibited bacteriological growth inhibition at concentration of less than 40.0μg/ml against both microorganisms. Compounds (7o) showed growth of inhibition at 2.5μg/ml against both microorganisms. Additional challenging for all compounds at lower concentrations is mandatory to compare their activity through standard Streptomycin at its MIC to get exact MIC the manufactured combinations. Thus it can be concluded that designed 1, 3, 4-oxadiazole derivatives (7a-v) were manufactured successfully using planned synthetic outline. After manufactured the molecules were characterized using spectroscopy analysis and tested for the biological activity. All combinations showed anti-bacterial action at tested concentration against both gram positive and gram negative organisms and one of the compound 7o showed activity at concentration <2.5 μg/ml. Thus, these 1, 3, 4-oxadiazole results can then act as a potential principal for drug discovery of novel anti-infective agents.

Invasive Sino-Orbital Aspergillosis in an Immunocompetent Patient

Invasive aspergillosis that involves intra-orbital and intracranial extension occurs in immunodeficient and immunocompetent patients resulting in significant morbidity and mortality. We report the case of a 38year old farmer who had recurrent fronto-ethmoidal mucocoele and proptosis of the left eye. She presented with a history of hypertension and no other significant findings on examination. Computer tomography scan of the brain showed a left fronto-orbital uniform contrast-enhancing extra-axial lesion with thickened peripheral capsule and an associated left fronto-orbital skull defect. Cerebrospinal fluid analysis did not show any sign of infection. Intra-operative biopsy sample showed cheesy material which on culture grew Aspergillus species that was identified further using molecular methods. Antifungal agents were used to treat the patient. The present case strongly suggests that it is possible to control intracranial aspergillosis with a combination of surgery and antifungal chemotherapy.

Invasive Sino-Orbital Aspergillosis in an Immunocompetent Patient

Invasive aspergillosis that involves intra-orbital and intracranial extension occurs in immunodeficient and immunocompetent patients resulting in significant morbidity and mortality. We report the case of a 38year old farmer who had recurrent fronto-ethmoidal mucocoele and proptosis of the left eye. She presented with a history of hypertension and no other significant findings on examination. Computer tomography scan of the brain showed a left fronto-orbital uniform contrast-enhancing extra-axial lesion with thickened peripheral capsule and an associated left fronto-orbital skull defect. Cerebrospinal fluid analysis did not show any sign of infection. Intra-operative biopsy sample showed cheesy material which on culture grew Aspergillus species that was identified further using molecular methods. Antifungal agents were used to treat the patient. The present case strongly suggests that it is possible to control intracranial aspergillosis with a combination of surgery and antifungal chemotherapy.

Invasive Sino-Orbital Aspergillosis in an Immunocompetent Patient

Invasive aspergillosis that involves intra-orbital and intracranial extension occurs in immunodeficient and immunocompetent patients resulting in significant morbidity and mortality. We report the case of a 38year old farmer who had recurrent fronto-ethmoidal mucocoele and proptosis of the left eye. She presented with a history of hypertension and no other significant findings on examination. Computer tomography scan of the brain showed a left fronto-orbital uniform contrast-enhancing extra-axial lesion with thickened peripheral capsule and an associated left fronto-orbital skull defect. Cerebrospinal fluid analysis did not show any sign of infection. Intra-operative biopsy sample showed cheesy material which on culture grew Aspergillus species that was identified further using molecular methods. Antifungal agents were used to treat the patient. The present case strongly suggests that it is possible to control intracranial aspergillosis with a combination of surgery and antifungal chemotherapy.

Invasive Sino-Orbital Aspergillosis in an Immunocompetent Patient

Invasive aspergillosis that involves intra-orbital and intracranial extension occurs in immunodeficient and immunocompetent patients resulting in significant morbidity and mortality. We report the case of a 38year old farmer who had recurrent fronto-ethmoidal mucocoele and proptosis of the left eye. She presented with a history of hypertension and no other significant findings on examination. Computer tomography scan of the brain showed a left fronto-orbital uniform contrast-enhancing extra-axial lesion with thickened peripheral capsule and an associated left fronto-orbital skull defect. Cerebrospinal fluid analysis did not show any sign of infection. Intra-operative biopsy sample showed cheesy material which on culture grew Aspergillus species that was identified further using molecular methods. Antifungal agents were used to treat the patient. The present case strongly suggests that it is possible to control intracranial aspergillosis with a combination of surgery and antifungal chemotherapy.

Invasive Sino-Orbital Aspergillosis in an Immunocompetent Patient

Invasive aspergillosis that involves intra-orbital and intracranial extension occurs in immunodeficient and immunocompetent patients resulting in significant morbidity and mortality. We report the case of a 38year old farmer who had recurrent fronto-ethmoidal mucocoele and proptosis of the left eye. She presented with a history of hypertension and no other significant findings on examination. Computer tomography scan of the brain showed a left fronto-orbital uniform contrast-enhancing extra-axial lesion with thickened peripheral capsule and an associated left fronto-orbital skull defect. Cerebrospinal fluid analysis did not show any sign of infection. Intra-operative biopsy sample showed cheesy material which on culture grew Aspergillus species that was identified further using molecular methods. Antifungal agents were used to treat the patient. The present case strongly suggests that it is possible to control intracranial aspergillosis with a combination of surgery and antifungal chemotherapy.

255. Breakthrough Mucormycosis (BT-MCR) on Antifungals Having Mucorales Activity Portrays Worse Prognosis compared with BT-MCR on Mold-Active Antifungals with no Mucorales Activity

BackgroundBT-MCR is known to develop in the setting of agents having Aspergillus but no Mucorales activity. However, BT-MCR can occur even with the use of antifungals having with Mucorales activity in patients with hematologic malignancies and or stem cell transplant (HM).MethodsWe reviewed the records of HM patients treated for MCR (1994 to 2019) at MD Anderson Cancer Center. We identified patients with BT-MCR on antifungals having Mucorales activity: posaconazole (POSA), isavuconazole (ISA), and amphotericin B (AMB) (group A), and patients with BT-MCR on agents having Aspergillus but no Mucorales activity: voriconazole (VRC), itraconazole (ITZ), echinocandins (group B). BT-MCR was defined as MCR diagnosis (dx) after ≥7days (d) of antifungal use. The primary outcome was 42d mortality after the BT-MCR dx. Chi-square or Fisher’s exact test was used for categorical variables and Wilcoxon rank-sum test used for continuous variables. Cox regression model was used to evaluate the independent variables on outcome.ResultsWe identified 11 patients in group A (3 POSA, 5 ISA, 3 AMB) and 81 patients in group B (61 VRC, 13 echinocandins, 7 ITZ). Both groups were not different in terms of age, sex, underlying HM (AML/MDS in 100% vs. 88% in groups A and B, respectively), status of HM (active disease in 82% vs. 67%), prior stem cell transplant (45% vs. 54%) or GvHD (80% vs. 84%), neutropenia at dx (55% vs. 42%), prior receipt of >600 mg of prednisone (45% vs. 41%) or ICU at MCR dx (36% vs. 26%). Similarly, Mucorales species (Rhizopus spp. in 55% vs. 49%) and type of infection (sino-pulmonary in 73% vs. 68%) were no different between the groups. However, both d42 (82% vs. 46%, P = 0.025) and d84 (100% vs. 60%, P = 0.007) mortality was worse in group A. Similarly, median time to death was faster in patients in group A (26d, range 7-80d), vs. group B (42d, range 4–3146d, P = 0.031). Kaplan–Meier analysis showed a similar difference (Figure 1). In multivariate analysis, neutropenia (P = 0.038) and ICU at dx (P = 0.002) were independent factors on day 42d mortality in all 92 patients with prior Mucorales–active antifungals showing a trend associated with poor outcome (P = 0.17).ConclusionBT-MCR on agents having Mucorales activity is a marker of poor prognosis in HM patients. Early use of investigational immunotherapy and salvage antifungal chemotherapy studies is needed in that subgroup of patients. Disclosures All authors: No reported disclosures.

Scedosporium spp lung infection in immunocompetent patients: A systematic review and MOOSE-compliant meta-analysis.

Scedosporium genus as a significant emerging opportunist causes a broad spectrum of disease in not only immunosuppressed but also immunocompetent patients. The lung is one of the most commonly encountered sites of Scedosporium infection. Due to its very high levels of antifungal resistance, surgery has been recommended as an important part in the treatment of pulmonary Scedosporium spp infection, even in immunocompetent cases. However, whether lung surgery could help to reduce the risk of death in immunocompetent patients is not clear.We retrospectively retrieved the records of pulmonary infections with Scedosporium species in immunocompetent patients through a comprehensive literature search. The association of surgery on all-cause mortality was explored using binary logistic regression (BLR). Receiver operating characteristic (ROC) curve analysis was carried out to evaluate the capability of the model.The comprehensive searching strategy yielded 33 case reports and 3 case series in total, with 40 individual patients being included. The overall mortality was 12.50%. The fatality rate was 9.09% (2/22) in cases with surgery and 16.67% (3/18) in cases without surgery (odds ratio, 0.50; 95% confidence interval, 0.07-3.38; P = .48). Consistently, BLR analysis identified no statistical association between surgery and reduced mortality (odds ratio, 1.19; 95% confidence interval, 0.09-15.64; P = .89), after adjusting for age, gender, and antifungal chemotherapy. The area under the ROC curve was 0.88.For immunocompetent patients with pulmonary Scedosporium spp infection, surgical therapy may not be associated with reduced mortality. Surgical excision could be considered but is not imperative in this group of patients.

A new acridone with antifungal properties against Candida spp. and dermatophytes, and antibiofilm activity against C. albicans.

The increase in the number of fungal infections worldwide, coupled with the limitations of current antifungal chemotherapy, demand the development of safe and effective new antifungals. Here, we presented the synthesis of a novel acridone (M14) and its antifungal properties against Candida and dermatophytes species. A series of 17 acridones was designed, synthesized and tested for its antifungal activity. The minimum inhibitory concentration (MIC) was determined by the broth microdilution method. Only the acridone M14 showed growth-inhibitory activity against reference strains and clinical isolates of Candida and dermatophytes, with MIC range of 7·81-31·25µgml-1 . Moreover, M14 exhibited fungicidal activity and prevented biofilm formation by C. albicans as well as reduced the viability of preformed biofilms, even at sub-MICs. The confocal laser scanning microscopy analysis revealed that C. albicans hyphal growth was completely inhibited in the presence of M14. Similarly, there was a severe inhibition on hyphal growth of Trichophyton rubrum. We also found that M14 has relatively low toxicity to human fibroblasts. The new acridone M14 has antifungal properties against Candida spp. and dermatophytes, and antibiofilm activity against C. albicans. In addition, M14 is relatively selective to fungal cells compared to human normal cells. Because of its in vitro antifungal activity, anti-Candida biofilm effect and moderate cytotoxicity towards normal human cell, M14 may serve as a valuable lead compound to develop a new antifungal agent.

Outcomes of endoscopic sinus surgery for sinusitis-induced intracranial abscess in patients undergoing neurosurgery.

Although sinusitis-induced intracranial complications rarely occur in the current era of antibiotics, they can induce neurological symptoms or death. The authors of this study investigated the association between endoscopic sinus surgery (ESS) and outcomes in patients who had undergone neurosurgical procedures for sinusitis-induced intracranial abscess. The authors obtained data on patients with sinusitis-induced intracranial abscess from the Japanese Diagnosis Procedure Combination inpatient data for the period from 2010 to 2017. They excluded patients with fungal sinusitis, orbital complications, immunodeficiency, and malignant disease. They also excluded patients who had received antifungal agents, chemotherapy, immunosuppressants, and antidiabetic drugs. Eligible patients were divided into those with and those without neurosurgical procedures. Propensity score-adjusted regression analyses were performed to examine the association between ESS within the same hospitalization and outcomes (mortality, blood transfusion, readmission, revision neurosurgery, and length of stay). Of the 552 potentially eligible patients, 255 were treated with neurosurgical procedures, including 104 who underwent ESS within the same hospitalization and 151 who did not. ESS was not significantly associated with mortality (OR 0.54, 95% CI 0.05-5.81, p = 0.61), blood transfusion (OR 1.95, 95% CI 0.84-4.51, p = 0.12), readmission (OR 0.86, 95% CI 0.34-2.16, p = 0.75), revision neurosurgery (OR 0.65, 95% CI 0.24-1.74, p = 0.39), or length of stay (percent difference -10.8%, 95% CI -24.4% to 5.1%, p = 0.18). The present study suggests that ESS may not have significant benefits with respect to reducing mortality, blood transfusion, readmission, revision neurosurgery, or length of stay.

Inflammatory Cell Recruitment in Candida glabrata Biofilm Cell-Infected Mice Receiving Antifungal Chemotherapy.

(1) Background: Due to a high rate of antifungal resistance, Candida glabrata is one of the most prevalent Candida spp. linked to systemic candidiasis, which is particularly critical in catheterized patients. The goal of this work was to simulate a systemic infection exclusively derived from C. glabrata biofilm cells and to evaluate the effectiveness of the treatment of two echinocandins—caspofungin (Csf) and micafungin (Mcf). (2) Methods: CD1 mice were infected with 48 h-biofilm cells of C. glabrata and then treated with Csf or Mcf. After 72 h, the efficacy of each drug was evaluated to assess the organ fungal burden through colony forming units (CFU) counting. The immune cell recruitment into target organs was evaluated by flow cytometry or histopathology analysis. (3) Results: Fungal burden was found to be higher in the liver than in the kidneys. However, none of the drugs was effective in completely eradicating C. glabrata biofilm cells. At the evaluated time point, flow cytometry analysis showed a predominant mononuclear response in the spleen, which was also evident in the liver and kidneys of the infected mice, as observed by histopathology analysis. (4) Conclusions: Echinocandins do not have a significant impact on liver and kidney fungal burden, or recruited inflammatory infiltrate, when mice are intravenously (i.v.) infected with C. glabrata biofilm-grown cells.

Rhinocerebral mucormycosis: A prospective analysis of an effective treatment protocol

Objective:The objective of this study was to prospectively analyze the effectiveness of a treatment protocol in patients diagnosed with rhinocerebral mucormycosis.Materials and Methods:This series included ten patients who reported with suspicious clinical signs of mucormycosis. The diagnosis was established by histopathology, and computed tomography imaging was used to assess the extent of spread. All patients were treated with immediate radical surgical debridement and antifungal chemotherapy with amphotericin B. Simultaneous correction of the underlying immunosuppressive condition was carried out. The primary outcome assessed was disease-free survival, and the patients were followed up for up to 6 months after discharge.Results:In this series, the cause of immunosuppression was uncontrolled diabetes mellitus in all patients. All the patients responded to the treatment protocol and were free of the disease up to 6 months of follow-up.Conclusion:Mucormycosis is an invasive and potentially fatal disease. Prognosis can be improved by early recognition and prompt treatment with aggressive resection, intravenous amphotericin B, and control of the patient's underlying systemic condition.

Intracranial Fungal Infections: Overview from Two Large Tertiary Hospital in Upper Egypt and Literature Review

Purpose: Fungal infections of the central nervous system (CNS) are potentially lethal conditions with high morbidity and mortality. In this review, we summarise the most common clinical manifestations, diagnostic methods, and treatment strategies for intracranial fungal infection at two tertiary care teaching hospitals. Material and methods: Prospective hospital study is carried out at Department of Neurosurgery; Assiut and Suhaj University Hospitals between January2010 to January 2018 (Minimum 12-months follow-up). Radiographs and hospital data of 74 patients with proven intracranial fungal infections were gathered and analyzed. There were no exclusion criteria: age, gender, clinical presentations, immunity status, radiological findings, laboratory, and microbiological data, types of management and outcome. In surgically treated patients, diagnosis was confirmed by pathologic evaluation. Gathered data were coded and entered into a computer and analyzed using SPSS version 22. Results: The greatest number of the patients had 40 to 60 years old (49; 66%) and the mean age was 44 years. There was an overwhelming male patient’s ranged preponderance 66%; 49 cases. Sixty-three patients (85%) were immunosuppressed; 11 cases (15%) were immunocompetent. The most common causes of immunosuppression were diabetes 27 patients; 43%, on chemotherapeutic agents 19 patients; 31%, on corticosteroid 16 patients; 25% and AIDS in one patient; 1%. Five different fungal types were identified but Cryptococcus spp. was the most common cause of CNS fungal infection, occurring in 39 patients (53%). This was followed by Candida spp. in 14 patients (19%), Aspergillus in 11 patients (15%), Blastomyces in 7 patients (9%) and Coccidiosis in 3 patients (4%). Headache was the most common presenting symptom, occurring in 33 patients (45%). Other relatively common symptoms were nausea or vomiting 11 patients (15%), fever 10 patients; (13%), seizures 9 patients (12%), acute mental status changes 8 patients; (11%) and stroke like Symptoms 3patients (4%). Different surgical procedures were done. Stereotactic biopsy is in 19 patients (deep; located in an eloquent region of the brain or multiple small lesion) or excision in 38 patients (cortical, relatively accessible regions of the brain), and CSF shunting in 17 patients. All patients received parenteral and, in some cases, oral antifungal chemotherapy in addition to surgical therapy. Overall mortality was 52.7% (39 deaths). An additional 8 surviving patients exhibited permanent morbidity due to neurological deficits and seizure disorders. Conclusion: This prospective population study demonstrates an insight into the intracranial fungal infection and management. CNS fungal infections have increased in frequency, particularly in immunocompromised patients; most infections are caused by Cryptococcus spp. Diabetes was the most common cause of immunosuppression and headache was the most common symptom at presentation. CNS fungal infection is still associated with a high mortality and morbidity. Prompt diagnosis; early and appropriate medical and surgical management are fundamental to optimize the outcome.

Systemic Antifungal Agents

Fungal infections remain an important cause of morbidity and mortality in surgical settings, with critically ill patients, transplant recipients, and sick neonates all especially vulnerable. Fungal infections remain an important cause of morbidity and mortality in surgical settings, with critically ill patients, transplant recipients, and sick neonates all especially vulnerable. Despite the development of a number of new and useful antifungal agents in the past decade and the noteworthy improvements in therapeutic approaches to fungal infections, physicians’ ability to diagnose these infections in a timely fashion remains limited, and patient outcomes remain poor. Antifungal prophylaxis has emerged as a potential means of reducing the occurrence of serious fungal infections. In patient populations estimated to be at high risk for acquiring a fungal infection, antifungal prophylaxis has reduced infection rates by about 50%; however, it has not been shown to significantly improve mortality. This review discusses both established and newly approved systemic antifungal agents. Tables list characteristics of currently available antifungals and antifungal chemotherapy. This review contains 2 tables and 32 references Key words: antifungal chemotherapy, antifungal prophylaxis, antifungals, Candida prophylaxis, systemic antifungal medications

Systemic Antifungal Agents

Fungal infections remain an important cause of morbidity and mortality in surgical settings, with critically ill patients, transplant recipients, and sick neonates all especially vulnerable. Fungal infections remain an important cause of morbidity and mortality in surgical settings, with critically ill patients, transplant recipients, and sick neonates all especially vulnerable. Despite the development of a number of new and useful antifungal agents in the past decade and the noteworthy improvements in therapeutic approaches to fungal infections, physicians’ ability to diagnose these infections in a timely fashion remains limited, and patient outcomes remain poor. Antifungal prophylaxis has emerged as a potential means of reducing the occurrence of serious fungal infections. In patient populations estimated to be at high risk for acquiring a fungal infection, antifungal prophylaxis has reduced infection rates by about 50%; however, it has not been shown to significantly improve mortality. This review discusses both established and newly approved systemic antifungal agents. Tables list characteristics of currently available antifungals and antifungal chemotherapy. This review contains 2 tables and 32 references Key words: antifungal chemotherapy, antifungal prophylaxis, antifungals, Candida prophylaxis, systemic antifungal medications

The Fungal Cell Wall: Structure, Biosynthesis, and Function.

The molecular composition of the cell wall is critical for the biology and ecology of each fungal species. Fungal walls are composed of matrix components that are embedded and linked to scaffolds of fibrous load-bearing polysaccharides. Most of the major cell wall components of fungal pathogens are not represented in humans, other mammals, or plants, and therefore the immune systems of animals and plants have evolved to recognize many of the conserved elements of fungal walls. For similar reasons the enzymes that assemble fungal cell wall components are excellent targets for antifungal chemotherapies and fungicides. However, for fungal pathogens, the cell wall is often disguised since key signature molecules for immune recognition are sometimes masked by immunologically inert molecules. Cell wall damage leads to the activation of sophisticated fail-safe mechanisms that shore up and repair walls to avoid catastrophic breaching of the integrity of the surface. The frontiers of research on fungal cell walls are moving from a descriptive phase defining the underlying genes and component parts of fungal walls to more dynamic analyses of how the various components are assembled, cross-linked, and modified in response to environmental signals. This review therefore discusses recent advances in research investigating the composition, synthesis, and regulation of cell walls and how the cell wall is targeted by immune recognition systems and the design of antifungal diagnostics and therapeutics.

Microevolution of Serial Clinical Isolates ofCryptococcus neoformansvar.grubiiandC. gattii

ABSTRACTThe pathogenic species of Cryptococcus are a major cause of mortality owing to severe infections in immunocompromised as well as immunocompetent individuals. Although antifungal treatment is usually effective, many patients relapse after treatment, and in such cases, comparative analyses of the genomes of incident and relapse isolates may reveal evidence of determinative, microevolutionary changes within the host. Here, we analyzed serial isolates cultured from cerebrospinal fluid specimens of 18 South African patients with recurrent cryptococcal meningitis. The time between collection of the incident isolates and collection of the relapse isolates ranged from 124 days to 290 days, and the analyses revealed that, during this period within the patients, the isolates underwent several genetic and phenotypic changes. Considering the vast genetic diversity of cryptococcal isolates in sub-Saharan Africa, it was not surprising to find that the relapse isolates had acquired different genetic and correlative phenotypic changes. They exhibited various mechanisms for enhancing virulence, such as growth at 39°C, adaptation to stress, and capsule production; a remarkable amplification of ERG11 at the native and unlinked locus may provide stable resistance to fluconazole. Our data provide a deeper understanding of the microevolution of Cryptococcus species under pressure from antifungal chemotherapy and host immune responses. This investigation clearly suggests a promising strategy to identify novel targets for improved diagnosis, therapy, and prognosis.

Glucose modulates antimicrobial photodynamic inactivation of Candida albicans in biofilms

Candida albicans biofilm is a main cause of infections associated with medical devices such as catheters, contact lens and artificial joint prosthesis. The current treatment comprises antifungal chemotherapy that presents low success rates. Photodynamic inactivation (PDI) involves the combination of a photosensitizing compound (PS) and light to generate oxidative stress that has demonstrated effective antimicrobial activity against a broad-spectrum of pathogens, including C. albicans. This fungus senses glucose inducing an upregulation of membrane transporters that can facilitate PS uptake into the cell. The aim of this study was to evaluate the effects of glucose on methylene blue (MB) uptake and its influence on PDI efficiency when combined to a red LED with central wavelength at λ=660nm. C. albicans biofilms were grown on hydrogel disks. Prior to PDI assays, MB uptake tests were performed with and without glucose-sensitization. In this system, the optimum PS administration was determined as 500μM of MB in contact with the biofilm during 30min before irradiation. Irradiation was performed during 3, 6, 9, 12, 15 and 18min with irradiance of 127.3mW/cm2. Our results showed that glucose was able to increase MB uptake in C. albicans cells. In addition, PDI without glucose showed a higher viability reduction until 6min; after 9min, glucose group demonstrated a significant decrease in cell viability when compared to glucose-free group. Taken together, our data suggest that glucose is capable to enhance MB uptake and modulate photodynamic inactivation of C. albicans biofilm.

Chitosan silver nanocomposite (CAgNC) as an antifungal agent againstCandida albicans

Due to limited numbers of antifungal drugs and emergence of drug resistance have directed to develop nonconventional therapeutic agents against fungal pathogen Candida albicans. In this study, anticandidal activity of chitosan silver nanocomposite (CAgNC) was tested against C. albicans Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of CAgNC were determined as 25 and 100μg/ml, respectively. Electron microscopic image results confirmed the ultrastructural cell wall deformities and injuries caused by CAgNC. Propidium iodide (PI) penetration into the CAgNC treated cells could be considered as an evidence for loss of cell membrane integrity and cell death at MFC. Level of intracellular reactive oxygen species (ROS) was increased, while cell viability was decreased with the increased of CAgNC concentrations. In our protein profile results, several induced proteins were observed under CAgNC treatment, and they could be related to multidrug and stress resistant proteins such as CDR1 (55kDa) and CaHSP70 based on the protein band size. CAgNC mediated cell wall damage, loss of cell membrane integrity, elevated ROS level, and associated oxidative stress have been identified as the main causative factors for the anticandidal activity. Overall results from our study indicated that CAgNC could affect negatively on physiological and biochemical functions of C. albicans suggesting CAgNC as a potential alternative for antifungal chemotherapy.