Oral complaints in patients with acute myeloid leukemia treated with allogeneic hematopoietic stem cell transplantation

Acute myeloid leukemia belongs to proliferative diseases of the hematopoietic system. It is currently the leading indication for allogeneic hematopoietic stem cell transplantation. This study was designed to determine the most common subjective oral mucosa complaints in patients with acute myeloid leukemia after allogeneic hematopoietic cell transplantation, in relation to the type of conditioning used. Eighty patients diagnosed with acute myeloid leukemia were assigned to two groups depending on the intensity of the conditioning regimen before transplantation: myeloablative and reduced-intensity chemotherapy. The oral symptoms were evaluated based on an authorial questionnaire designed for this analysis. The following oral mucosa subjective complaints were included: pain, paraesthesia, burning mouth sensation, taste disorders, excessive salivation, halitosis, and dryness of the oral mucosa. The most commonly reported subjective oral complaint in the examined patients was xerostomia, which was found in 92% of patients during the second visit, followed by spontaneous pain in the mouth (55%), burning (36%), and dysgeusia (20%). It occurred significantly more frequently in patients who underwent myeloablative conditioning. Moreover, it was observed that the frequency of complaints increased considerably after the transplantation, reaching a peak intensity during the second week following the procedure. Oral complaints significantly decrease the patients' quality of life during the transplantation and may lead to premature termination of the treatment. As the number of transplantations in patients with acute myeloid leukemia increases, further investigations of oral complaints and symptoms induced by the disease itself and by the therapeutic approaches are required

AmBisome inhibits the adherence of Candida albicans to HeLa cells

Objectives: Candidal adherence to epithelial cells is significantly reduced when antifungal polyenes are present during the “adherence phase”, but the treatment does not result in detachment of cell-associated yeasts. It has been reported that Candida biofilms with reduced susceptibility to conventional antifungals, are sensitive to lipid formulations of amphotericin B (AMB). Here we examined the effect of AmBisome, the liposomal AMB formulation, and free AMB on the adherence of C. albicans to HeLa cells. Methods: The adherence of C. albicans to HeLa cells was determined as described by Samaranayake et al. (1994). Cells were either incubated with Candida in the presence of the drug or pre-incubated with yeasts for 1 hr at 37°C and subsequently exposed to the drug. The cytotoxic effect of the drugs on HeLa cells was determined by an Alamar Blue assay. Results: AmBisome was not toxic in the range 1 – 256 µg/ml, while AMB was toxic above 4 µg/ml. Following the 1 hr incubation, in the presence of AMB at 1 and 4 µg/ml, the adherence of C. albicans was reduced by 58 and 71%, respectively. Under these conditions, AmBisome at 1, 4, 16, 64 and 256 µg/ml reduced adherence by 54, 63, 70, 76, and 83%, respectively. These values were significantly different from the controls (P \u3c 0.0005). The susceptibility of cell-associated Candida to AMB and AmBisome was significantly lower. The reduction in adherence was between 4 and 10%, when compared to the drug-free controls. The values obtained for AmBisome at 16, 64 and 256 µg/ml were significantly different from the controls (P \u3c 0.05). Conclusions: The liposomal AMB formulation, AmBisome, which is not toxic in a wide range of concentrations, inhibits candidal colonization when present during the “adherence phase”, while the cell-associated Candida yeasts are highly resistant to antifungals in terms of adherence

AmBisome and amphotericin B inhibit the initial adherence of Candida albicans to human epithelial cell lines, but do not cause yeast detachment

Background: Candida biofilms with reduced susceptibility to conventional antifungals are sensitive to lipid formulations of amphotericin B (AMB). We examined the effect of the liposomal AMB formulation, AmBisome, and free AMB on the adherence of C. albicans to HeLa cervical carcinoma and HSC-3 oral squamous cell carcinoma cells. Material/Methods: HeLa and HSC-3 cells were incubated with three oral isolates of C. albicans either in the presence of AmBisome or AMB, or pre-incubated with yeasts and subsequently exposed to the drug. The effect of the drugs on the viability of HeLa and HSC-3 cells was determined by an Alamar Blue assay . Results: Following a 1-h incubation in the presence of AmBisome, at 1-256 μg/ml, the adherence of C. albicans to HeLa and HSC-3 cells was reduced considerably. For example at 16 μg/ml, adherence was diminished by ~66% in HeLa and by ~36% in HSC-3 cells. The susceptibility of cell-associated Candida to antifungals was decreased markedly. The reduction in adherence was between 3.3 and 13.7%, when compared to the drug-free controls. AmBisome was not toxic in the range 1-256 μg/ml, while free AMB was not toxic at 1 and 4 μg/ml to HeLa cells and at 1, 4 and 16 μg/ml to HSC-3 cells. Conclusions: AmBisome inhibited candidal attachment when present during the adherence phase but did not cause detachment of cell-associated yeasts. The effect of AmBisome on candidal adherence to HSC-3 cells was less inhibitory than that observed with HeLa cells. Candidal adherence to epithelial cells is significantly reduced when antifungal polyenes are present during the adherence phase , while cell-associated Candida is resistant to antifungals in terms of adherence. © Med Sci Monit, 2009

The influence of antifungal polyenes on in vitro adherence of Candida to epithelial cells

Objectives: Oral candidiasis is the most common opportunistic infection in immunocompromised patients. The antifungal polyenes are commonly used for the treatment of oral candidiasis. Since adherence of microorganisms to mucosal surfaces is required for successful colonization and subsequent infection, the aim of this study was to assess quantitatively the influence of antifungal polyenes (amphotericin B, nystatin, natamycin) on in vitro adherence of Candida albicans ATTC 44990 and Candida glabrata ATCC MYA-275 to human epithelial cell monolayers. Methods: The adherence of yeasts to HeLa or HSC-3 cell monolayers was assessed according to the method of Samaranayake et al. (J Med Microbiol 1994, 41:230-238) with the addition of antimycotics at minimum inhibitory or sublethal concentrations, or with no drug addition (controls). Results: Significant reduction of candidal adherence was observed when antifungal polyenes were used, except in the case of C. glabrata adherence to HeLa cells for nystatin at the minimum inhibitory concentration. The suppressive effect against two Candida strains was highest for amphotericin B, and nystatin elicited the lowest efficacy. Conclusions: The present data, the first on the effect of antifungal polyenes, indicate that minimum inhibitory and sublethal concentration of amphotericin B, nystatin and natamycin suppress in vitro adherence of Candida to epithelial cell monolayers. These studies were supported by grant from the Kosciuszko Foundation, New York, USA

AmBisome and amphotericin B inhibit the initial adherence of Candida albicans to human epithelial cell lines, but do not cause yeast detachment

Background: Candida biofilms with reduced susceptibility to conventional antifungals are sensitive to lipid formulations of amphotericin B (AMB). We examined the effect of the liposomal AMB formulation, AmBisome, and free AMB on the adherence of C. albicans to HeLa cervical carcinoma and HSC-3 oral squamous cell carcinoma cells. Material/Methods: HeLa and HSC-3 cells were incubated with three oral isolates of C. albicans either in the presence of AmBisome or AMB, or pre-incubated with yeasts and subsequently exposed to the drug. The effect of the drugs on the viability of HeLa and HSC-3 cells was determined by an Alamar Blue assay . Results: Following a 1-h incubation in the presence of AmBisome, at 1-256 μg/ml, the adherence of C. albicans to HeLa and HSC-3 cells was reduced considerably. For example at 16 μg/ml, adherence was diminished by ~66% in HeLa and by ~36% in HSC-3 cells. The susceptibility of cell-associated Candida to antifungals was decreased markedly. The reduction in adherence was between 3.3 and 13.7%, when compared to the drug-free controls. AmBisome was not toxic in the range 1-256 μg/ml, while free AMB was not toxic at 1 and 4 μg/ml to HeLa cells and at 1, 4 and 16 μg/ml to HSC-3 cells. Conclusions: AmBisome inhibited candidal attachment when present during the adherence phase but did not cause detachment of cell-associated yeasts. The effect of AmBisome on candidal adherence to HSC-3 cells was less inhibitory than that observed with HeLa cells. Candidal adherence to epithelial cells is significantly reduced when antifungal polyenes are present during the adherence phase , while cell-associated Candida is resistant to antifungals in terms of adherence. © Med Sci Monit, 2009

Influence of antifungal polyenes on the adhesion of Candida albicans and Candida glabrata to human epithelial cells in vitro

Candidal adherence to mucosal surfaces is considered as the first step in the pathogenesis of oral candidiasis. We examined the effect of antifungal polyenes, amphotericin B, nystatin and natamycin, at sublethal and minimum inhibitory concentrations (MICs) on the adherence of Candida albicans and Candida glabrata to HeLa cervical carcinoma and HSC-3 oral squamous cell carcinoma cells. A total of six oral Candida isolates were used throughout the study. Two Candida strains, C. albicans (44990) and C. glabrata (MYA-275) were obtained from ATCC. Four Candida strains, C. albicans 19 and 24 and C. glabrata 15 and 21, were isolated from patients with documented Candida-associated denture stomatitis. Cells were either incubated with Candida in the presence of the drug, or pre-incubated with yeasts and exposed subsequently to the drug. In the drug-free controls, the mean number of C. albicans yeasts associated with HeLa cells obtained from all experiments (130.1 ± 10.1 yeasts/ mm 2) was significantly greater than that for HSC-3 cells (114.7 ± 10.1 yeasts/mm2; P \u3c 0.025). For C. glabrata, the mean adherence to HeLa and HSC-3 cells was 84.4 ± 5.5 and 84.4 ± 3.3 yeasts/mm2, respectively, and these values were not statistically different (P \u3e 0.4). Candidal adherence was significantly reduced when the tested polyenes were present during the adherence phase . The obtained values were significantly different from the controls, except for the effect of nystatin at the MIC on the adherence of C. glabrata strain MYA-275 to HeLa cells (P \u3c 0.375). Amphotericin B had the highest effect against both Candida species, reducing adherence by ∼50 and ∼60%, at the MIC and sublethal concentrations, respectively. The susceptibility of cell-associated Candida to polyenes was decreased markedly and the treatment did not result in significant detachment of adherent yeasts. The reduction in adherence was between 2 and 10%, when compared to the drug-free controls. These findings suggest that sub-therapeutic levels of polyenes that are likely to persist in the oral cavity following topical treatment may modulate candidal colonization when present during the adherence phase . © 2003 Elsevier Ltd. All rights reserved

Positive Effects of UV-Photofunctionalization of Titanium Oxide Surfaces on the Survival and Differentiation of Osteogenic Precursor Cells—An In Vitro Study

Introduction: The UVC-irradiation (“UV-photofunctionalization”) of titanium dental implants has proved to be capable of removing carbon contamination and restoring the ability of titanium surfaces to attract cells involved in the process of osteointegration, thus significantly enhancing the biocompatibility of implants and favoring the post-operative healing process. To what extent the effect of UVC irradiation is dependent on the type or the topography of titanium used, is still not sufficiently established. Objective: The present study was aimed at analyzing the effects of UV-photofunctionalization on the TiO2 topography, as well as on the gene expression patterns and the biological activity of osteogenic cells, i.e., osteogenic precursors cultured in vitro in the presence of different titanium specimens. Methodology: The analysis of the surface roughness was performed by atomic force microscopy (AFM) on machined surface grade 2, and sand-blasted/acid-etched surface grades 2 and 4 titanium specimens. The expression of the genes related with the process of healing and osteogenesis was studied in the MC3T3-E1 pre-osteoblastic murine cells, as well as in MSC murine stem cells, before and after exposure to differently treated TiO2 surfaces. Results: The AFM determinations showed that the surface topographies of titanium after the sand-blasting and acid-etching procedures, look very similar, independently of the grade of titanium. The UVC-irradiation of the TiO2 surface was found to induce an increase in the cell survival, attachment and proliferation, which was positively correlated with an increased expression of the osteogenesis-related genes Runx2 and alkaline phosphatase (ALP). Conclusion: Overall, our findings expand and further support the current view that UV-photofunctionalization can indeed restore biocompatibility and osteointegration of TiO2 implants, and suggest that this at least in part occurs through a stimulation of the osteogenic differentiation of the precursor cells

Evaluation of serum zinc levels in patients with recurrent aphthous stomatitis (RAS)

Abstract Background Recurrent aphthous stomatitis (RAS) is an ulcerative disease of the oral mucosa without a clearly defined etiology. The aim of the study was to evaluate the serum zinc levels in patients with RAS in comparison to healthy controls and to validate the association between zinc levels and the course of RAS. Methods Seventy-five patients with RAS and 72 controls underwent full dental examination. Serum zinc levels were determined by flame atomic absorption spectroscopy (F AAS). The results were statistically analyzed with Kruskal-Wallis, Mann-Whitney, chi-square tests and the test of difference between the two rates of structure with p < 0.05 as a significance level (Statistica 10, StatSoft®). Results No statistically significant differences were detected in serum zinc levels between RAS patients and healthy controls. The mean serum zinc concentration was found to be 84.2 μg/dL in RAS group and 83.9 μd/dL in controls, within the accepted norms. Zinc deficiency was observed in 10.7% patients from the RAS group and in 6.9% controls. No significant differences in serum zinc levels were found between patients when the course of the disease was considered. Conclusions Serum zinc concentrations did not differ significantly in RAS patients and in healthy controls and it did not influence the course of the disease. Therefore, zinc does not appear to be an important modifying factor in the development of RAS