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Human Oral Cavity (human + oral_cavity)

Distribution by Scientific Domains

Medical Sciences	75%

Selected Abstracts

Helicobacter pylori in human oral cavity and stomach

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 4 2008
Ralf Bürgers
The oral cavity has been suspected as an extra-gastroduodenal reservoir for Helicobacter pylori infection and transmission, but conflicting evidence exists regarding the occurrence of H. pylori in the mouth, independently of stomach colonization. Ninety-four gastric biopsy patients were analysed for the concurrent presence of H. pylori in the mouth and stomach. Samples were collected from different areas within the mouth and H. pylori DNA was amplified by the polymerase chain reaction (PCR) and verified by sequencing. Helicobacter pylori -specific serology was performed, and stomach colonization was determined by culture. In addition, relevant dental and periodontal parameters, as well as general health parameters, were recorded. Helicobacter pylori was found in the stomach of 29 patients and in the oral cavity of 16 patients. In only six patients was the bacterium detected simultaneously in the stomach and mouth. Notably, the 10 patients in whom the bacterium was found solely in the mouth did not have serum antibodies to H. pylori. The occurrence of H. pylori in the mouth was found to be correlated neither to any general or oral health parameters, nor to any particular site of collection. This study shows that H. pylori can occur in the oral cavity independently of stomach colonization. [source]

Interactions between salivary Bifidobacterium adolescentis and other oral bacteria: in vitro coaggregation and coadhesion assays

FEMS MICROBIOLOGY LETTERS, Issue 2 2008
Seiji Nagaoka
Abstract Coaggregation assays were performed to investigate interactions between oral Bifidobacterium adolescentis and other oral bacterial species. Bifidobacterium adolescentis OLB6410 isolated from the saliva of healthy humans did not coaggregate with Actinomyces naeslundii JCM8350, Streptococcus mitis OLS3293, Streptococcus sanguinis JCM5708, Veillonella parvula ATCC17745 or Porphyromonas gingivalis OB7124, but it did coaggregate with Fusobacterium nucleatum JCM8532. Subsequent examination of biofilm formation on saliva-coated hydroxyapatite discs using FISH revealed that B. adolescentis OLB6410 could not directly adhere to the coated discs. It did, however, adhere to biofilms of A. naeslundii, V. parvula, and F. nucleatum, although it did not coaggregate with A. naeslundii nor with V. parvula. These results suggest that the adhesion of B. adolescentis to tooth surfaces is mediated by other oral bacteria. Heat- or proteinase K-treated F. nucleatum could not coaggregate with B. adolescentis. Similarly, the coaggregation and coadhesion of proteinase K-treated B. adolescentis were strongly inhibited. It is therefore probable that proteinaceous factors on the cellular surface of B. adolescentis and F. nucleatum are involved in their interaction. The data presented in this study add to our understanding of bifidobacterial colonization in the human oral cavity. [source]

Coaggregation of Streptococcus salivarius with periodontopathogens: evidence for involvement of fimbriae in the interaction with Prevotella intermedia

MOLECULAR ORAL MICROBIOLOGY, Issue 5 2003
C. Lévesque
Streptococcus salivarius is divided into two serological subgroups that carry either fibrils or fimbriae. Although fimbriae have been observed on up to 50% of S. salivarius strains in the human oral cavity, no function has yet been assigned to them. To determine whether S. salivarius fimbriae have a role in adhesion, we examined the ability of S. salivarius to coaggregate with selected microorganisms involved in periodontal diseases. Our results show that S. salivarius coaggregated with Fusobacterium nucleatum, Porphyromonas gingivalis, and Prevotella intermedia. However, only fimbriated S. salivarius cells were able to coaggregate with P. intermedia, suggesting a specific role for these structures in the interaction. Heat treatment, sensitivity to sugars, amino acids, and EDTA, as well as protease treatment were also used to further characterize coaggregation between S. salivarius and periodontopathogens. [source]

Rothia dentocariosa sepsis in a pediatric renal transplant recipient having post-transplant lymphoproliferative disorders

PEDIATRIC TRANSPLANTATION, Issue 3 2006
Silke Wiesmayr
Abstract: Background: Rothia dentocariosa (RD) is a Gram-positive rod that colonizes the human oral cavity and can cause infective endocarditis. Result: We report on a six-yr-old boy who underwent renal transplantation for polycystic kidney disease at the age of eight months. He developed post-transplant lymphoproliferative disorders after four yr and progressive graft failure. Following chemotherapy, the patient presented with neutropenia and sepsis. RD was isolated from blood and treatment with piperacillin/tazobactam was initiated; however, the child died because of multiorgan failure. Discussion: To the best of our knowledge, this is the first case of RD sepsis in a pediatric solid organ transplant recipient. [source]