Molecular Analysis of ApiA, a Multi-Functional Protein.

ApiA is a trimeric autotransporter outer membrane protein (Omp) that participates in multiple functions, enabling to adapt to a variety of environments. The goal of this study is to identify regions in the gene responsible for three of these functions: auto-aggregation, buccal epithelial cell binding, and complement resistance. Initially, was expressed in .

A Rose by Any Other Name: The Long Intricate History of Localized Aggressive Periodontitis.

This review addresses the recent World Workshop Consensus Conference (WWCC) decision to eliminate Localized Aggressive Periodontitis (LAgP) in young adults as a distinct form of periodontitis. A "Consensus" implies widespread, if not unanimous, agreement among participants. However, a significant number of attendees were opposed to the elimination of the LAgP classification.

Oral microbial interactions from an ecological perspective: a narrative review.

Landscape ecology is a relatively new field of study within the sub-specialty of ecology that considers time and space in addition to structure and function. Landscape ecology contends that both the configuration (spatial pattern) and the composition (organisms both at the macro and or micro level) of an ecology can change over time. The oral cavity is an ideal place to study landscape ecology because of the variety of landscapes, the dynamic nature of plaque biofilm development, and the easy access to biofilm material.

Aggregatibacter, A Low Abundance Pathobiont That Influences Biogeography, Microbial Dysbiosis, and Host Defense Capabilities in Periodontitis: The History of A Bug, And Localization of Disease.

the focus of this review, was initially proposed as a microbe directly related to a phenotypically distinct form of periodontitis called localized juvenile periodontitis. At the time, it seemed as if specific microbes were implicated as the cause of distinct forms of disease. Over the years, much has changed.

NADPH Oxidase Contributes to Resistance against Aggregatibacter actinomycetemcomitans-Induced Periodontitis in Mice.

Aggregatibacter actinomycetemcomitans is a Gram-negative commensal bacterium of the oral cavity which has been associated with the pathogenesis of periodontitis with severe alveolar bone destruction. The role of host factors such as reactive oxygen and nitrogen intermediates in periodontal A. actinomycetemcomitans infection and progression to periodontitis is still ill-defined.

Role of exopolysaccharide in Aggregatibacter actinomycetemcomitans-induced bone resorption in a rat model for periodontal disease.

Aggregatibacter actinomycetemcomitans a causative agent of periodontal disease in humans, forms biofilm on biotic and abiotic surfaces. A. actinomycetemcomitans biofilm is heterogeneous in nature and is composed of proteins, extracellular DNA and exopolysaccharide.

Bacterial infection increases periodontal bone loss in diabetic rats through enhanced apoptosis.

Periodontal disease is the most common osteolytic disease in humans and is significantly increased by diabetes mellitus. We tested the hypothesis that bacterial infection induces bone loss in diabetic animals through a mechanism that involves enhanced apoptosis. Type II diabetic rats were inoculated with Aggregatibacter actinomycetemcomitans and treated with a caspase-3 inhibitor, ZDEVD-FMK, or vehicle alone.

A comparison of Aggregatibacter actinomycetemcomitans (Aa) virulence traits in a rat model for periodontal disease.

Our aim was to explore the effects of Cytolethal Distending toxin (Cdt) in a well established rat model of periodontal disease where leukotoxin (LtxA) was thought to have no known effect. In vitro studies, were used to assess CdtB activity using Aa Leukotoxin as a negative control. These studies showed that both CdtB and LtxA (unexpectedly) exerted significant effects on CD4(+) T cells.

Aggregatibacter actinomycetemcomitans infection enhances apoptosis in vivo through a caspase-3-dependent mechanism in experimental periodontitis.

The purpose of this study was to test the hypothesis that diabetes aggravates periodontal destruction induced by Aggregatibacter actinomycetemcomitans infection. Thirty-eight diabetic and 33 normal rats were inoculated with A. actinomycetemcomitans and euthanized at baseline and at 4, 5, and 6 weeks after inoculation.

A.actinomycetemcomitans-induced periodontal disease promotes systemic and local responses in rat periodontium.

Aim: To characterize the histologic and cellular response to A. actinomycetemcomitans (Aa) infection.

Material & Methods: Wistar rats infected with Aa were evaluated for antibody response, oral Aa colonization, loss of attachment, PMN recruitment, TNF-α in the junctional epithelium and connective tissue, osteoclasts and adaptive immune response in local lymph nodes at baseline and 4, 5 or 6 weeks after infection.

Aggregatibacter actinomycetemcomitans-induced bone loss and antibody response in three rat strains.

Background: The aim of this study is to compare the colonization, immunoglobulin (Ig) G response, and alveolar bone loss in Aggregatibacter actinomycetemcomitans (Aa)-inoculated Fawn Hooded Hypertensive (FHH), Dahl Salt-Sensitive (DSS), and Brown Norway (BN) rats.

Methods: Each rat strain was divided into wild-type Aa-inoculated and non-inoculated control groups. Blood taken at 12 weeks after inoculation was assessed for Aa-specific IgG antibodies by an enzyme-linked immunosorbent assay.

An improved cost-effective, reproducible method for evaluation of bone loss in a rodent model.

Aim: This study was designed to investigate the utility of two "new" definitions for assessment of bone loss in a rodent model of periodontitis.

Material And Methods: Eighteen rats were divided into three groups. Group 1 was infected by Aggregatibacter actinomycetemcomitans (Aa), group 2 was infected with an Aa leukotoxin knock-out, and group 3 received no Aa (controls).

Toothbrush bristle wear and adherence of Streptococcus mutans.

Purpose: The purpose of this study was conducted to determine if bristle wear impacts the adherence of Streptococcus mutans on toothbrushes and to evaluate whether it affects the extent of adherence at 0, 8, and 24 hours after air-drying.

Methods: Sixty toothbrushes--composed of 20 each from 3 different groups and defined by brand, brush trim, and head shape--were used in this study. Bristle wear on half of the toothbrushes was achieved using an orthodontic typodont with metal bonds and brackets and evaluated by 4 independent observers.

Tight-adherence genes of Actinobacillus actinomycetemcomitans are required for virulence in a rat model.

Actinobacillus actinomycetemcomitans is a Gram-negative coccobacillus that has been associated with localized aggressive periodontitis and infections of the heart, brain, and urinary tract. Wild-type clinical isolates have the remarkable ability to adhere tenaciously and nonspecifically to solid surfaces such as glass, plastic, and hydroxyapatite. Adherence by A.

Population structure and genetic diversity of Actinobacillus actinomycetemcomitans strains isolated from localized juvenile periodontitis patients.

The phylogeny of 20 Actinobacillus actinomycetemcomitans strains isolated from patients with localized juvenile periodontitis (LJP) was investigated by using partial sequence analysis of 16S rRNA genes, arbitrarily primed PCR (AP-PCR), and four additional PCR assays that amplified polymorphic regions in the leukotoxin (lkt), cytolethal distending toxin (cdt), major fimbrial subunit (flp-1), and serotype-specific O polysaccharide gene clusters. Our analysis also included four strains isolated from healthy subjects and nine reference strains. We found that A.

Phenotypic variation in Actinobacillus actinomycetemcomitans during laboratory growth: implications for virulence.

This study examined alteration of specific virulence traits associated with phenotypic changes seen when a low-passage disease-associated and well maintained parent strain of Actinobacillus actinomycetemcomitans was compared to a laboratory-grown spontaneous variant/mutant. Clinical isolates of A. actinomycetemcomitans recovered from periodontitis patients typically grow as rough, adherent colonies on primary culture but undergo transformation to smooth, non-adherent colonies following repeated passage in vitro.