DNA fingerprinting elicited evolutionary trend of oral Candida tropicalis isolates from diverse geographic locales.

Purpose: To study molecular profiles of oral Candida tropicalis isolates from five different geographic locales to determine the molecular diversity, clonality and evolutionary trends of this opportunistic pathogen.

Methods: A total of 36 strains from five countries (China, Canada, Scotland, Japan and Tanzania) were genotyped by PCR fingerprinting with 11 separate primers. Of these, primers RSG9, RSG8, T3B and RSD12 generated complex fingerprinting patterns.

Hyphal invasion of Candida albicans inhibits the expression of human beta-defensins in experimental oral candidiasis.

Oral epithelium reacts to microbial challenges by eliciting a defensive response that includes the production of antimicrobial peptides. This study investigated the expression of human beta-defensins-1, 2, and 3 in reconstituted human oral epithelia during experimental oral infections with six different Candida species, and a wild-type C. albicans isolate and five of its mutants.

Interspecies variation in Candida biofilm formation studied using the Calgary biofilm device.

An in vitro assay to study multiple Candida biofilms, in parallel, has been carried out using the Calgary biofilm device (CBD). We here report: i) standardization of the CBD for Candida albicans biofilm formation, ii) kinetics of C. albicans biofilm formation, iii) biofilm formation by five Candida species, and iv) effect of dietary carbohydrates on biofilm formation.

Diabetes mellitus as a contributory factor in oral candidosis.

It has been reported that poor glycaemic control predisposes to oral candidal infection in diabetic patients. For instance, the carriage of Candida species and the density of candidal growth in the oral cavity is frequently claimed to be increased in patients with diabetes mellitus. However, the validity of these observations remains controversial.

(B1) Candida and mycotic infections.

Oral candidiasis (OC) is the most common mucosal manifestation of HIV infection. This workshop examined OC and other mycoses associated with HIV infection. Historically, blood CD4 cell numbers were the primary prognosticator for the development of OC.

Effect of oral bacteria on growth and survival of Candida albicans biofilms.

The purpose of this study was to evaluate the effect of eight aerobic and anaerobic oral commensal bacterial species on in vitro Candida albicans biofilm development. A single isolate of C. albicans 2560 g, and eight different species of oral bacteria comprising, Actinomyces israelii, Lactobacillus acidophilus, Prevotella nigrescens, Porphyromonas gingivalis, Pseudomonas aeruginosa, Escherichia coli, Streptococcus mutans, and Streptococcus intermedius were studied using an in vitro biofilm assay.

Application of an interactive computer program to manage a problem-based dental curriculum.

Managing the change from traditional to problem-based learning (PBL) curricula is complex because PBL employs problem cases as the vehicle for learning. Each problem case covers a wide range of different learning issues across many disciplines and is coordinated by different facilitators drawn from the school's multidisciplinary pool. The objective of this project was to adapt an interactive computer program to manage a problem-based dental curriculum.

In vitro adhesion of Candida species to denture base materials.

Adhesion of Candida species to prosthetic acrylic resins is an essential first step in the pathogenesis of denture stomatitis. Data on the relative adhesion of pathogenic non-albicans Candida species to different denture base materials are sparse. The purpose of the present study was to investigate in vitro adhesion of C.

Identification of cultivable microorganisms from root canals with apical periodontitis following two-visit endodontic treatment with antibiotics/steroid or calcium hydroxide dressings.

The study was aimed at comparing the efficacy of disinfection of root canals with periapical radiolucencies when treated with either antibiotics/steroid medicaments (Ledermix or Septomixine) or a calcium hydroxide paste (Calasept). Microbiological samples were taken before and after two-visit endodontic treatment from 88 canals with apical periodontitis. All of the canals but one (87 of 88) had cultivable growth before treatment.

In vitro antifungal effect of amine fluoride-stannous fluoride combination on oral Candida species.

Objective: The combination of amine fluoride and stannous fluoride (AmF/SnF2) was, by chance, found to be antifungal in a clinical trial. This study investigated its effect on pathogenic Candida species with the hypothesis that the antifungal action on different species is variable.

Materials And Methods: Growth inhibition effect of Meridol mouth rinse which contains 250 ppm AmF/SnF2 was evaluated on 43 reference and clinical strains of Candida albicans, C.

Expression of human beta-defensin-3 in gingival epithelia.

Objective: This study aimed to investigate the expression patterns of the newly discovered human beta-defensin-3 (hBD-3) in human gingiva.

Background: Human beta-defensins (hBDs) are a group of small, broad-spectrum, cationic antimicrobial peptides. Our recent study showed that the expression levels of hBD-1 and 2 peptides were associated with periodontal conditions.

Clindamycin in dentistry: more than just effective prophylaxis for endocarditis?

Clindamycin is a broad-spectrum antibiotic with activity against aerobic, anaerobic, and beta-lactamase-producing pathogens. This antibiotic has been used for many years as prophylactic treatment during dental procedures to prevent endocarditis. However, the spectrum and susceptibility of the bacteria species involved in dental infections indicate that clindamycin would also be an effective treatment option for these conditions.

Characterization of switch phenotypes in Candida albicans biofilms.

The aim of this study was to characterize switch phenotypes in Candida albicans biofilms. Cells of Candida albicans 192887g biofilms (24 h) were resuspended and these together with their planktonic counterparts were separately inoculated on Lee's medium agar supplemented with arginine and zinc, at 25 degrees C for 9 days, for colony formation. The different switch phenotypes, as reflected by varying colony morphologies, were then examined for their (i) stability under various growth conditions, (ii) carbohydrate assimilation profiles, (iii) susceptibility to the polyene antifungal, nystatin, (iv) adhering and biofilm-forming ability, (v) filamentation, and (vi) growth rate in yeast nitrogen base medium supplemented with 100 mM glucose.

Identification of cultivable microorganisms from primary endodontic infections with exposed and unexposed pulp space.

This study was aimed at comparing the cultivable microorganisms in canals with periapical radiolucencies with exposed and unexposed pulp space. Microbiological samples were taken and analyzed from 45 canals with exposed pulp space, and 43 canals with unexposed pulp space. The canal contents were analyzed by aerobic/anaerobic culture, and conventional identification techniques.

Phospholipase B enzyme expression is not associated with other virulence attributes in Candida albicans isolates from patients with human immunodeficiency virus infection.

The extracellular phospholipases of Candida albicans are considered to play a significant role in the pathogenesis of human infections. Therefore 30 clinical isolates of C. albicans from human immunodeficiency virus (HIV)-infected individuals were screened for phospholipase production in vitro (using an egg-yolk-agar medium).

The use of new probes and stains for improved assessment of cell viability and extracellular polymeric substances in Candida albicans biofilms.

Phenotypic and genotypic cell differentiation is considered an important feature that confers enhanced antifungal resistance in candidal biofilms. Particular emphasis has been placed in this context on the viability of biofilm subpopulations, and their heterogeneity with regard to the production of extracellular polymeric substances (EPS). We therefore assessed the utility of two different labeled lectins Erythrina cristagalli (ECA) and Canavalia ensiformis (ConA), for EPS visualization.

Frequent allelic loss of 21q11.1 approximately q21.1 region in advanced stage oral squamous cell carcinoma.

A fine mapping of loss of heterozygosity (LOH) was performed in oral squamous cell carcinoma (OSCC), using 12 markers on 21q11.1 approximately q21.1.

An ultrastructural and a cytochemical study of candidal invasion of reconstituted human oral epithelium.

Background: Opportunistic yeast, Candida albicans causes superficial and systemic mycoses in compromised patients. Adhesion to host tissues, morphogenesis and extracellular phospholipases (PL) are thought to contribute to its virulence. The nature of numerous host-parasite interactions at the invasive phase of oral candidiasis is not fully understood.

Oral Candida species and betel quid-associated oral lesions in Padaung women of Northern Thailand.

Purpose of the present investigation was to study the association between the betel quid chewing (BQC) habits, the oral yeast flora and oral lesions in female Padaung of northern Thailand. Oral swabs were taken from the tongue and palate of 50 Padaung women with and 50 control individuals without BQC habit. The spectrum of oral Candida species in both groups was determined microbiologically.

In vitro method to study antifungal perfusion in Candida biofilms.

Antimycotic perfusion through Candida biofilms was demonstrated by a modification of a simple in vitro diffusion cell bioassay system. Using this model, the perfusion of three commonly used antifungal agents, amphotericin B, fluconazole, and flucytosine, was investigated in biofilms of three different Candida species (i.e.

The effect of fixed orthodontic appliances on the oral carriage of Candida species and Enterobacteriaceae.

The aim of this investigation was to evaluate the prevalence of Candida and Enterobacteriaceae in a group of adolescents during fixed orthodontic appliance (FOA) therapy. The experimental group was recruited from a larger sample of orthodontic patients who were clinically examined once to obtain baseline data before active treatment. The group comprised 27 subjects; 13 males, 14 females (mean age 15.

Coaggregation profiles of the microflora from root surface caries lesions.

Bacterial coaggregation reactions between different species and the auto aggregation of the same species are associated with the initiation and development of dental plaque and biofilms. As no such data is available on isolates from root caries lesions, we evaluated, by a visual, semi-quantitative scoring system and a spectrophotometric, quantitative assay, the coaggregation of 22 different wild-type microbial species comprising ten bacterial genera and a single Candida spp. The quantitative coaggregation assay we used proved to be a more sensitive method than the semi-quantitative, visual evaluation as the results yielded the percent coaggregation.

Molecular evaluation of residual endodontic microorganisms after instrumentation, irrigation and medication with either calcium hydroxide or Septomixine.

Background And Objective: The correct choice of antimicrobial agents as inter-appointment medicaments is as important as the instrumentation and irrigation to remove pathogens from infected root canals. Calcium hydroxide [Ca(OH)2] and framycetin sulfate (Septomixine) are common endodontic medicaments. Therefore, we evaluated the efficacy of either calcium hydroxide or Septomixine in eliminating residual intra-canal bacteria, particularly Actinomyces spp.

Cytotoxic drugs, radiotherapy and oral candidiasis.

The increased incidence of oral candidiasis in patients with malignancies stems partly from the systemic disease itself and, partly from the therapeutic measures such as cytotoxic and other immunosuppressive drugs and radiotherapy they receive during management of such malignancies. In this review we discuss the clinical and laboratory findings on the relationship between cytotoxics, radiotherapy and oral candidiasis, possible mechanisms of pathogenicity following such therapy, as well as precautions that could be taken to minimize such recalcitrant yeast infections.

Oral candidosis and associated Candida species in HIV-infected Cambodians exposed to antimycotics.

Although human immundeficiency virus (HIV) infection is endemic in Southeast Asia, data on oral mycotic flora in this disease in Asians are sparse. The aim of this study was to determine the prevalence of Candida species in HIV-infected Cambodians with oral candidosis, unexposed (group 1) and exposed to antimycotics (group 2) and a healthy population (group 3). In 161 HIV patients with oral candidosis (group 1: 121 pts; group 2: 40 pts) and in 81 controls (group 3) swab samples of tongue and palate were obtained.