Evaluating clinical utility of subgingival and salivary endotoxin activity levels as periodontal biomarkers.

Objectives: The use of periodontal biomarkers for identification and monitoring of unique patient populations could foster better stratification of at-risk groups, increase access to treatment for those most in need, facilitate preventive measures and improve personalised care plans. The aim of this study was to examine the diagnostic and prognostic utility of oral lipopolysaccharides as bacterially-derived periodontal biomarkers.

Methods: Periodontal parameters were recorded, and saliva and subgingival plaque samples were collected at the beginning of the study from periodontally healthy volunteers and periodontitis patients, and three months after completion of conventional periodontal treatment in the periodontitis group.

Periodontitis and cardiometabolic disorders: The role of lipopolysaccharide and endotoxemia.

Lipopolysaccharide is a virulence factor of gram-negative bacteria with a crucial importance to the bacterial surface integrity. From the host's perspective, lipopolysaccharide plays a role in both local and systemic inflammation, activates both innate and adaptive immunity, and can trigger inflammation either directly (as a microbe-associated molecular pattern) or indirectly (by inducing the generation of nonmicrobial, danger-associated molecular patterns). Translocation of lipopolysaccharide into the circulation causes endotoxemia, which is typically measured as the biological activity of lipopolysaccharide to induce coagulation of an aqueous extract of blood cells of the assay.

Comparative analysis of total salivary lipopolysaccharide chemical and biological properties with periodontal status.

Objective: Clinical manifestations of Gram-negative bacteria mediated diseases can be influenced by how the host senses their major microbe-associated molecular pattern, the cell wall lipopolysaccharide (LPS). Keystone periodontal pathogens can produce a heterogeneous population of LPS molecules, with strikingly different host-microbiome interactions and immune outcomes.

Design: Structure-function correlations of salivary LPS extracts in patients with periodontitis before and after periodontal treatment and healthy volunteers were analysed by comparing its lipid A and carbohydrate chain chemical structure and evaluating its endotoxin activity and inflammatory potential.

Effect of constant versus variable small-group facilitators on students' basic science knowledge in an enquiry-based dental curriculum.

Introduction: The role of small-group facilitators is of pivotal importance for the success of curricula based on active learning. Disorganised tutorial processes and superficial study of the problem have been identified as main hindering factors for students' learning. The aim of this study was to evaluate the influence of consistency of facilitation on students' performance in knowledge-based basic science assessments in a hybrid, enquiry-based (EBL) undergraduate dental curriculum.

Subgingival lipid A profile and endotoxin activity in periodontal health and disease.

Objectives: Regulation of lipopolysaccharide (LPS) chemical composition, particularly its lipid A domain, is an important, naturally occurring mechanism that drives bacteria-host immune system interactions into either a symbiotic or pathogenic relationship. Members of the subgingival oral microbiota can critically modulate host immuno-inflammatory responses by synthesizing different LPS isoforms. The objectives of this study were to analyze subgingival lipid A profiles and endotoxin activities in periodontal health and disease and to evaluate the use of the recombinant factor C assay as a new, lipid A-based biosensor for personalized, point-of-care periodontal therapy.

The benefits of integrating dental and dental therapy and hygiene students in undergraduate curricula.

Purpose: The purpose of the current study was to evaluate the impact of integrating the teaching of Bachelor of Dental Surgery (BDS) and Bachelor of Dental Therapy and Hygiene (BScDTH) students in enquiry-based learning (EBL) sessions, using performance on multiple related integrated dental science (IDS) multiple-choice question assessments.

Method: IDS assessments are sat twice in the first stages of both the BDS and BScDTH programmes. IDS scores from integrated and non-integrated cohorts were collated and compared across test occasions (first or second assessment of the stage) and programmes (BDS and BScDTH).

Sialylation of Porphyromonas gingivalis LPS and its effect on bacterial-host interactions.

Porphyromonas gingivalis produces different LPS isoforms with significant structural variations of their lipid A and O-antigen moieties that can affect its pro-inflammatory and bone-resorbing potential. We show here, for the first time, that P. gingivalis LPS isolated from W83 strain is highly sialylated and possesses significantly reduced inflammatory potential compared with less sialylated ATCC 33277 strain LPS.

Eradication of gastric Helicobacter pylori ameliorates halitosis and tongue coating.

Background: The influence of gastric Helicobacter pylori infection on the development of oral pathoses remains unclear. The aim of this study is to examine the influence of gastric H. pylori infection on occurrence of halitosis and coated tongue.

Altered Toll-like receptor 2-mediated endotoxin tolerance is related to diminished interferon beta production.

Induction of endotoxin tolerance leads to a reduced inflammatory response after repeated challenge by LPS and is important for resolution of inflammation and prevention of tissue damage. Enterobacterial LPS is recognized by the TLR4 signaling complex, whereas LPS of some non-enterobacterial organisms is capable of signaling independently of TLR4 utilizing TLR2-mediated signal transduction instead. In this study we report that Porphyromonas gingivalis LPS, a TLR2 agonist, fails to induce a fully endotoxin tolerant state in a human monocytic cell line (THP-1) and mouse bone marrow-derived macrophages.

Impaired immune tolerance to Porphyromonas gingivalis lipopolysaccharide promotes neutrophil migration and decreased apoptosis.

Periodontitis, a chronic inflammatory disease of the tissues supporting the teeth, is characterized by an exaggerated host immune and inflammatory response to periopathogenic bacteria. Toll-like receptor activation, cytokine network induction, and accumulation of neutrophils at the site of inflammation are important in the host defense against infection. At the same time, induction of immune tolerance and the clearance of neutrophils from the site of infection are essential in the control of the immune response, resolution of inflammation, and prevention of tissue destruction.