Oral Yeast (oral + yeast)

Distribution by Scientific Domains


Selected Abstracts


Yeast of the oral cavity is the reservoir of Heliobacter pylori

JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 6 2008
Ali-Hatef Salmanian
Background:, Frequent occurrence of Helicobacter pylori in the human gastrointestinal tract and its persistence due to unsuccessful antimicrobial therapy might be related to a stage in the life cycle of H. pylori in which the bacterium establishes itself as an intracellular symbiont in yeast. In this study, occurrence of non-culturable H. pylori in the oral yeast was assessed by targeting vacuolating cytotoxin A (vacA s1s2) and ureAB genes in the total DNAs of yeasts. Methods:, DNAs were extracted from 13 oral yeasts in which bacterium-like bodies, suspected to be H. pylori, were observed microscopically. Primers were recruited to amplify vacA s1s2 and ureAB genes. DNAs from H. pylori and E. coli were used as controls. The amplicons from one yeast and H. pylori were sequenced. Yeasts were identified as Candida albicans. Results:, Fragments of vacA s1s2 and ureAB genes were amplified from 13 yeasts. The size of PCR products was 286 bp for vacA s1s2 gene and 406 bp for ureAB gene. Similar bands were obtained from the control H. pylori, and the results for E. coli were negative. The data from sequencing of PCR products showed about 98% homology between the genes amplified from yeast and those from H. pylori. Conclusions:, The results of this study showed the intracellular occurrence of H. pylori in yeast. This endosymbiotic relationship might explain the persistence of H. pylori in the oral cavity, the consequence of which could be reinoculation of the stomach by the bacterium and spread of infection among human populations. [source]


Reducing the Incidence of Denture Stomatitis: Are Denture Cleansers Sufficient?

JOURNAL OF PROSTHODONTICS, Issue 4 2010
Anto Jose MSc
Abstract Purpose:,Candida albicans is the predominant oral yeast associated with denture stomatitis. With an increasing population of denture wearers, the incidence of denture stomatitis is increasing. Effective management of these patients will alleviate the morbidity associated with this disease. The aim of this study was to examine the capacity of four denture cleansers to efficiently decontaminate and sterilize surfaces covered by C. albicans biofilms. Materials and Methods: Sixteen C. albicans strains isolated from denture stomatitis patients and strain ATCC 90028 were grown as mature confluent biofilms on a 96-well format and immersed in Dentural, MedicalÔ Interporous®, Steradent Active Plus, and Boots Smile denture cleansers according to the manufacturers' instructions or overnight. The metabolic activity and biomass of the biofilms were then quantified, and scanning electron microscopy (SEM) used to examine treated biofilms. Results: Dentural was the most effective denture cleanser, reducing the biomass by greater than 90% after 20 minutes. Steradent Active plus was significantly more effective following 10-minute immersion than overnight (p < 0.001). All cleansers reduced the metabolic activity by greater than 80% following overnight immersion; however, Boots Smile exhibited significantly reduced metabolic activity following only a 15-minute immersion (p < 0.001). SEM revealed residual C. albicans material following Dentural treatment. Conclusions: This study showed that denture cleansers exhibit effective anti- C. albicans biofilm activity, both in terms of removal and disinfection; however, residual biofilm retention that could lead to regrowth and denture colonization was observed. Therefore, alternative mechanical disruptive methods are required to enhance biofilm removal. [source]


Yeast of the oral cavity is the reservoir of Heliobacter pylori

JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 6 2008
Ali-Hatef Salmanian
Background:, Frequent occurrence of Helicobacter pylori in the human gastrointestinal tract and its persistence due to unsuccessful antimicrobial therapy might be related to a stage in the life cycle of H. pylori in which the bacterium establishes itself as an intracellular symbiont in yeast. In this study, occurrence of non-culturable H. pylori in the oral yeast was assessed by targeting vacuolating cytotoxin A (vacA s1s2) and ureAB genes in the total DNAs of yeasts. Methods:, DNAs were extracted from 13 oral yeasts in which bacterium-like bodies, suspected to be H. pylori, were observed microscopically. Primers were recruited to amplify vacA s1s2 and ureAB genes. DNAs from H. pylori and E. coli were used as controls. The amplicons from one yeast and H. pylori were sequenced. Yeasts were identified as Candida albicans. Results:, Fragments of vacA s1s2 and ureAB genes were amplified from 13 yeasts. The size of PCR products was 286 bp for vacA s1s2 gene and 406 bp for ureAB gene. Similar bands were obtained from the control H. pylori, and the results for E. coli were negative. The data from sequencing of PCR products showed about 98% homology between the genes amplified from yeast and those from H. pylori. Conclusions:, The results of this study showed the intracellular occurrence of H. pylori in yeast. This endosymbiotic relationship might explain the persistence of H. pylori in the oral cavity, the consequence of which could be reinoculation of the stomach by the bacterium and spread of infection among human populations. [source]


Sjögren's syndrome sufferers have increased oral yeast levels despite regular dental care

ORAL DISEASES, Issue 2 2008
KCM Leung
Aim:, To investigate the prevalence and quantity of oral yeasts and their association with oral candidiasis in Sjögren's syndrome (SS) patients receiving regular dental care. Materials and methods:, Yeasts in oral rinse and full-mouth supra-gingival plaque samples from 25 primary SS, 27 secondary SS and 29 control subjects were selectively cultured. All yeasts except single-species isolates were genotyped using pulsed field gel electrophoresis (PFGE). Results:, Ten (19%) SS sufferers had symptomless candidiasis. SS subjects had a higher prevalence (73%vs 7%) and quantity of yeasts than controls in both oral rinse and plaque samples (P < 0.05). The prevalence of yeasts in plaque was associated with candidiasis regardless of denture wearing (P , 0.04). Candida albicans was the predominant yeast isolated. PFGE showed 20 (66% of total) C. albicans isolate pairs, i.e. C. albicans species isolated from plaque and oral rinse samples of the same individual, were of closely related genetic clonal types (P < 0.01). Conclusions:, Despite effective oral hygiene, more SS subjects than controls had detectable levels of oral yeasts and their presence in supra-gingival plaque was associated with candidiasis. Candida albicans colonized supra-gingival biofilm even in well-maintained SS individuals, posing a challenge to the control of oral candidiasis. [source]