Tannerella forsythia and Pseudomonas aeruginosa in subgingival bacterial samples from parous women

BACKGROUND: Information on the subgingival microbiota in parous women is limited. The present study assessed 74 bacterial species at periodontal sites. METHODS: Subgingival bacterial plaque was collected from women > or =6 months after delivery. Bacteria were assessed by the checkerboard DNA-DNA hybridization method. Gingivitis was defined as > or =20% of sites with bleeding on probing (BOP), and periodontitis was defined as radiographic evidence of bone loss and probing depths > or =5.0 mm. RESULTS: A total of 197 women (mean age: 29.4 +/- 6.8 years; range: 18 to 46 years) were included in the study. Gingivitis was identified in 82 of 138 subjects without evidence of periodontitis (59.4%). Periodontitis was found in 59 women (32%). Higher bacterial levels in subjects with gingivitis compared to those without evidence of gingivitis were observed for Actinomyces neuii, Bifidobacterium bifidum, Corynebacterium pseudogenitalis, Porphyromonas endodontalis, Prevotella bivia, and Pseudomonas aeruginosa (P <0.001 for each). Higher bacterial levels in subjects with periodontitis compared to those without periodontitis (BOP not accounted for) were found for 32 of 79 species (P <0.001) including Lactobacillus iners, Haemophilus influenzae, Porphyromonas gingivalis, Tannerella forsythia (previously T. forsythensis), Prevotella bivia, P. aeruginosa, and Staphylococcus aureus. Binary univariate logistic regression analysis identified that P. aeruginosa (P <0.001) and T. forsythia (P <0.05) were independently predictive of periodontal status. The odds ratio of having P. aeruginosa at levels > or =1 x 10(5) in the sample and periodontitis was 3.1 (95% confidence interval: 1.6 to 5.9; P <0.001). CONCLUSION: In addition to P. gingivalis and T. forsythia, a diverse microbiota, including P. aeruginosa, P. endodontalis, P. bivia, and S. aureus, can be found in subgingival plaque samples from women of child-bearing age with periodontitis.

Bifidobacterium lactis attenuates onset of inflammation in a murine model of colitis

To assess the anti-inflammatory effect of the probiotic Bifidobacterium lactis (B. lactis) in an adoptive transfer model of colitis.

PCR and real-time PCR primers developed for detection and identification of Bifidobacterium thermophilum in faeces

BACKGROUND: Culture-independent methods based on the 16S ribosomal RNA molecule are nowadays widely used for assessment of the composition of the intestinal microbiota, in relation to host health or probiotic efficacy. Because Bifidobacterium thermophilum was only recently isolated from human faeces until now, no specific real-time PCR (qPCR) assay has been developed for detection of this species as component of the bifidobacterial community of the human intestinal flora. RESULTS: Design of specific primers and probe was achieved based on comparison of 108 published bifidobacterial 16S rDNA sequences with the recently published sequence of the human faecal isolate B. thermophilum RBL67. Specificity of the primer was tested in silico by similarity search against the sequence database and confirmed experimentally by PCR amplification on 17 Bifidobacterium strains, representing 12 different species, and two Lactobacillus strains. The qPCR assay developed was linear for B. thermophilum RBL67 DNA quantities ranging from 0.02 ng/microl to 200 ng/microl and showed a detection limit of 10(5) cells per gram faeces. The application of this new qPCR assay allowed to detect the presence of B. thermophilum in one sample from a 6-month old breast-fed baby among 17 human faecal samples tested. Additionally, the specific qPCR primers in combination with selective plating experiments led to the isolation of F9K9, a faecal isolate from a 4-month old breast-fed baby. The 16S rDNA sequence of this isolate is 99.93% similar to that of B. thermophilum RBL67 and confirmed the applicability of the new qPCR assay in faecal samples. CONCLUSION: A new B. thermophilum-specific qPCR assay was developed based on species-specific target nucleotides in the 16S rDNA. It can be used to further characterize the composition of the bifidobacterial community in the human gastrointestinal tract. Until recently, B. thermophilum was considered as a species of animal origin, but here we confirm with the application of this new PCR assay the presence of B. thermophilum strains in the human gut.

Commensal and probiotic bacteria influence intestinal barrier function and susceptibility to colitis in Nod1-/-; Nod2-/- mice

The intestinal microbiota regulates key host functions. It is unknown whether modulation of the microbiota can affect a genetically determined host phenotype. Polymorphisms in the Nucleotide oligomerization domain (Nod)-like receptor family confer genetic risk for inflammatory bowel disease (IBD). We investigated whether the intestinal microbiota and the probiotic strain Bifidobacterium breve NCC2950 affect intestinal barrier function and responses to intestinal injury in Nod1(-/-); Nod2(-/-) mice.

Antibiotic susceptibility patterns and resistance genes of starter cultures and probiotic bacteria used in food

A survey of starter and probiotic cultures was carried out to determine the current antibiotic resistance situation in microbial food additives in Switzerland. Two hundred isolates from 90 different sources were typed by molecular and other methods to belong to the genera Lactobacillus (74 samples), Staphylococcus (33 samples), Bifidobacterium (6 samples), Pediococcus (5 samples), or were categorized as lactococci or streptococci (82 samples). They were screened for phenotypic resistances to 20 antibiotics by the disk diffusion method. Twenty-seven isolates exhibiting resistances that are not an intrinsic feature of the respective genera were further analyzed by microarray hybridization as a tool to trace back phenotypic resistances to specific genetic determinants. Their presence was finally verified by PCR amplification or Southern hybridization. These studies resulted in the detection of the tetracycline resistance gene tet(K) in 5 Staphylococcus isolates used as meat starter cultures, the tetracycline resistance gene tet(W) in the probiotic cultures Bifidobacterium lactis DSM 10140 and Lactobacillus reuteri SD 2112 (residing on a plasmid), and the lincosamide resistance gene lnu(A) (formerly linA) in L. reuteri SD 2112.

Effects of probiotic bacteria in dogs with food responsive diarrhoea treated with an elimination diet

We evaluated whether a probiotic supplementation in dogs with food responsive diarrhoea (FRD) has beneficial effects on intestinal cytokine patterns and on microbiota. Twenty-one client-owned dogs with FRD were presented for clinically needed duodeno- and colonoscopy and were enrolled in a prospective placebo (PL)-controlled probiotic trial. Intestinal tissue samples and faeces were collected during endoscopy. Intestinal mRNA abundance of interleukin (IL)-5, -10, -12p40 and -13, tumour necrosis factor-alpha, transforming growth factor-beta1 and interferon (IFN)-gamma were analysed and numbers of Lactobacillus spp., Bifidobacterium spp., Enterococcus spp. and Enterobacteriaceae and supplemented probiotic bacteria were determined in faeces. The Canine Inflammatory Bowel Disease Activity Index, a scoring system comprising general attitude, appetite, faecal consistency, defecation frequency, and vomitus, decreased in all dogs (p < 0.0001). Duodenal IL-10 mRNA levels decreased (p = 0.1) and colonic IFN-gamma mRNA levels increased (p = 0.08) after probiotic treatment. Numbers of Enterobacteriaceae decreased in FRD dogs receiving probiotic cocktail (FRD(PC)) and FRD dogs fed PL (FRD(PL)) during treatment (p < 0.05), numbers of Lactobacillus spp. increased in FRD(PC after) when compared with FRD(PC before) (p < 0.1). One strain of PC was detected in five of eight FRD(PC) dogs after probiotic supplementation. In conclusion, all dogs clinically improved after treatment, but cytokine patterns were not associated with the clinical features irrespective of the dietary supplementation.