Impact of Post-Exodontia Bleeding in Cardiovascular Patients: A New Classification Proposal.

BACKGROUND: Exodontia (dental extraction), being the most frequent minor surgical procedure in the general population, inevitably involves a large number of patients on antithrombotic medication. Current experience shows that there is a degree of confusion in managing these patients. DESCRIPTION: Post-exodontia bleeding, a natural consequence of every dental extraction with no or minor clinical significance in the vast majority of cases, often appears to be of major concern to both patients and healthcare practitioners (dentists or physicians), either because of the alarming nature of oral bleeding itself or because of the distorted perception about its importance. These concerns are enhanced by the lack of a universal standardized definition of post-exodontia bleeding and by the fact that all currently available post-exodontia bleeding definitions bear intrinsic limitations and tend to overestimate its clinical significance. CONCLUSION: In order to overcome the aforementioned issues, this article presents an overview of post-extraction bleeding and proposes a classification, based on the well-recognized Bleeding Academic Research Consortium (BARC) bleeding definition, aiming at reducing heterogeneity in this field.

Responses of anaerobic rumen fungal diversity (phylum Neocallimastigomycota) to changes in bovine diet.

AIMS: Anaerobic rumen fungi (Neocallimastigales) play important roles in the breakdown of complex, cellulose-rich material. Subsequent decomposition products are utilized by other microbes, including methanogens. The aim of this study was to determine the effects of dietary changes on anaerobic rumen fungi diversity. METHODS AND RESULTS: Altered diets through increasing concentrate/forage (50 : 50 vs 90 : 10) ratios and/or the addition of 6% soya oil were offered to steers and the Neocallimastigales community was assessed by PCR-based fingerprinting with specific primers within the barcode region. Both a decrease in fibre content and the addition of 6% soya oil affected Neocallimastigales diversity within solid and liquid rumen phases. The addition of 6% soya oil decreased species richness. Assemblages were strongly affected by the addition of 6% soya oil, whereas unexpectedly, the fibre decrease had less effect. Differences in volatile fatty acid contents (acetate, propionate and butyrate) were significantly associated with changes in Neocallimastigales assemblages between the treatments. CONCLUSIONS: Diet clearly influences Neocallimastigales assemblages. The data are interpreted in terms of interactions with other microbial groups involved in fermentation processes within the rumen. SIGNIFICANCE AND IMPACT OF THE STUDY: Knowledge on the influence of diet on anaerobic fungi is necessary to understand changes in microbial processes occurring within the rumen as this may impact on other rumen processes such as methane production.

The effect of dietary concentrate and soya oil inclusion on microbial diversity in the rumen of cattle.

AIMS: Methane emissions from ruminants are a significant contributor to global greenhouse gas production. The aim of this study was to examine the effect of diet on microbial communities in the rumen of steers. METHODS AND RESULTS: The effects of dietary alteration (50 : 50 vs 90 : 10 concentrate-forage ratio, and inclusion of soya oil) on methanogenic and bacterial communities in the rumen of steers were examined using molecular fingerprinting techniques (T-RFLP and automated ribosomal intergenic spacer analysis) and real-time PCR. Bacterial diversity was greatly affected by diet, whereas methanogen diversity was not. However, methanogen abundance was significantly reduced (P = 0.009) in high concentrate-forage diets and in the presence of soya oil (6%). In a parallel study, reduced methane emissions were observed with these diets. CONCLUSIONS: The greater effect of dietary alteration on bacterial community in the rumen compared with the methanogen community may reflect the impact of substrate availability on the rumen bacterial community. This resulted in altered rumen volatile fatty acid profiles and had a downstream effect on methanogen abundance, but not diversity. SIGNIFICANCE AND IMPACT OF THE STUDY: Understanding how rumen microbial communities contribute to methane production and how these microbes are influenced by diet is essential for the rational design of methane mitigation strategies from livestock.

Comparison of DNA- and RNA-based bacterial community structures in soil exposed to 2,4-dichlorophenol.

AIMS: To examine the effect of the pollutant 2,4-dichlorophenol on DNA- and RNA-based bacterial communities in soil. METHODS AND RESULTS: Soil was exposed to 100 mg kg(-1) of 2,4-dichlorophenol (2,4-DCP), and degradation was monitored over 35 days. DNA and RNA were coextracted, and terminal restriction fragment length polymorphism (T-RFLP) was used to report changes in bacterial communities in response to the presence of the chlorophenol. The phylogenetic composition of the soil during degradation was determined by creating a clone library of amplified 16S rRNA sequences from both DNA and reverse-transcribed RNA from exposed soil. Resulting clones were sequenced, and putative identities were assigned. CONCLUSIONS: A significant difference between active (RNA-based) and total (DNA-based) bacterial community structure was observed for both T-RFLP and phylogenetic analyses in response to 2,4-DCP, with more pronounced changes seen in RNA-based communities. Phylogenetic analysis indicated the dominance of Proteobacteria in both profiles. SIGNIFICANCE AND IMPACT OF THE STUDY: This study describes the response of soil bacterial communities to the addition of the xenobiotic compound 2,4-DCP, and highlights the importance of including RNA-based 16S rRNA analysis to complement any molecular study in a perturbed soil.

Tumour necrosis factor-alpha (TNF-alpha) increases nuclear factor kappaB (NFkappaB) activity in and interleukin-8 (IL-8) release from bovine mammary epithelial cells.

Epithelia play important immunological roles at a variety of mucosal sites. We examined NFkappaB activity in control and TNF-alpha treated bovine mammary epithelial monolayers (BME-UV cells). A region of the bovine IL-8 (bIL-8) promoter was sequenced and a putative kappaB consensus sequence was identified bioinformatically. We used this sequence to analyse nuclear extracts for IL-8 specific NFkappaB activity. As a surrogate marker of NFkappaB activation, we investigated IL-8 release in two models. Firstly in BME-UV monolayers, IL-8 release in the presence of pro- and anti-inflammatory agents was determined by enzyme-linked immunosorbent assay (ELISA). Secondly, we measured IL-8 secretion from a novel model of intact mucosal sheets of bovine teat sinus. IL-8 release into bathing solutions was assessed following treatment with pro- and anti-inflammatory agents. TNF-alpha enhanced NFkappaB activity in bovine mammary epithelial monolayers. p65 NFkappaB homodimer was identified in both control and TNF-alpha treated cells. Novel sequencing of the bovine IL-8 promoter identified a putative kappaB consensus sequence, which specifically bound TNF-alpha inducible p50/p65 heterodimer. TNF-alpha induced primarily serosal IL-8 release in the cell culture model. Pre-treatment with anti-TNF or dexamethasone inhibited TNF-alpha induced IL-8 release. High dose interleukin-1beta (IL-1beta) induced IL-8 release, however significantly less potently than TNF-alpha. Bovine mammary mucosal tissue released high basal levels of IL-8 which were unaffected by TNF-alpha or IL-1beta but inhibited by both dexamethasone and anti-TNF. These data support a role for TNF-alpha in activation of NFkappaB and release of IL-8 from bovine mammary epithelial cells.

Vascular reactivity in patients with peripheral vascular disease.

Noninvasive techniques have been used to demonstrate a specific pattern of impaired vasoactive response in the normal brachial artery of patients with clinical atherosclerosis. This is a physiologic reflection of the systemic nature of atherosclerosis and may be useful as a marker for identifying patients with preclinical atherosclerotic disease.

Hemodynamics of seasonal adaptation.

To investigate the possibility that seasonal adaptation requires significant hemodynamic changes, 5 normotensive and 21 mildly hypertensive subjects were followed through 4 seasons for changes in systemic hemodynamics and sympathetic nervous activity. In the upright position wintertime blood pressures increased by 3% (P = NS) over summer values whereas cardiac output and stroke volume decreased by 18% and 21%, respectively (P less than .0017 for each). Similarly, wintertime upright heart rate increased by 7% (P less than .017) with larger parallel increases in systemic vascular resistance (+24%, P less than .0017) and plasma norepinephrine (+26%, P less than .017). The supine values followed similar trends but the magnitude of changes was about 50% less than the corresponding upright values. Thus, in the northern US, wintertime vasoconstriction is related to increased sympathetic nervous activity and decreased cardiac output. When these reciprocal changes are proportional, blood pressure remains constant.