Publications by authors named "Dashper S"

Information generated from longitudinally-sampled microbial data has the potential to illuminate important aspects of development and progression for many human conditions and diseases. Identifying microbial biomarkers and their time-varying effects can not only advance our understanding of pathogenetic mechanisms, but also facilitate early diagnosis and guide optimal timing of interventions. However, longitudinal predictive modeling of highly noisy and dynamic microbial data (e.

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Periodontitis is a common chronic inflammatory disease, affecting approximately 19% of the global adult population. A relationship between periodontal disease and Alzheimer disease has long been recognized, and recent evidence has been uncovered to link these 2 diseases mechanistically. Periodontitis is caused by dysbiosis in the subgingival plaque microbiome, with a pronounced shift in the oral microbiota from one consisting primarily of Gram-positive aerobic bacteria to one predominated by Gram-negative anaerobes, such as Porphyromonas gingivalis.

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Periodontitis is a chronic inflammatory disease driven by dysbiosis in subgingival microbial communities leading to increased abundance of a limited number of pathobionts, including Porphyromonas gingivalis and Treponema denticola. Oral health, particularly periodontitis, is a modifiable risk factor for Alzheimer disease (AD) pathogenesis, with components of both these bacteria identified in postmortem brains of persons with AD. Repeated oral inoculation of mice with P.

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Background: Social disadvantage leads to dental caries during childhood.

Aim: This study investigated whether dental caries occur earlier in children from households experiencing social disadvantage than those not experiencing social disadvantage.

Design: The overall risk of, and relative time to, early childhood caries (ECC) according to sociodemographic characteristics in Victoria, Australia, was quantified.

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Despite recent advances in the development of orthopedic devices, implant-related failures that occur as a result of poor osseointegration and nosocomial infection are frequent. In this study, we developed a multiscale titanium (Ti) surface topography that promotes both osteogenic and mechano-bactericidal activity using a simple two-step fabrication approach. The response of MG-63 osteoblast-like cells and antibacterial activity toward and bacteria was compared for two distinct micronanoarchitectures of differing surface roughness created by acid etching, using either hydrochloric acid (HCl) or sulfuric acid (HSO), followed by hydrothermal treatment, henceforth referred to as either MN-HCl or MN-HSO.

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The cause of Alzheimer's disease (AD), and the pathophysiological mechanisms involved, remain major unanswered questions in medical science. Oral bacteria, especially those species associated with chronic periodontitis and particularly , are being linked causally to AD pathophysiology in a subpopulation of susceptible individuals. produces large amounts of proteolytic enzymes, haem and iron capture proteins, adhesins and internalins that are secreted and attached to the cell surface and concentrated onto outer membrane vesicles (OMVs).

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Objective: To assess the longitudinal trends in social inequalities in early childhood caries (ECC) using collected population-based data.

Methods: Clinical data on children were routinely collected from 2008 to 2019 in Victoria, Australia. ECC prevalence and severity (dmft) were quantified according to Indigenous status, culturally and linguistically diverse (CALD) status, concession cardholder status, geographic remoteness and area deprivation.

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Background: Pre-clinical evidence implicates oral bacteria in the pathogenesis of Alzheimer's disease (AD), while clinical studies show diverse results.

Objective: To comprehensively assess the association between oral bacteria and AD with clinical evidence.

Methods: Studies investigating the association between oral bacteria and AD were identified through a systematic search of six databases PubMed, Embase, Cochrane Central Library, Scopus, ScienceDirect, and Web of Science.

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Oral carcinogenesis is preceded by oral diseases associated with inflammation such as periodontitis and oral candidiasis, which are contributed by chronic alcoholism, smoking, poor oral hygiene, and microbial infections. Dysbiosis is an imbalance of microbial composition due to oral infection, which has been reported to contribute to oral carcinogenesis. Therefore, in this review, we summarised the role of probiotics, prebiotics, synbiotics, and postbiotics in promoting a balanced oral microbiome, which may prevent oral carcinogenesis due to oral infections.

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Background: Human microbiomes assemble in an ordered, reproducible manner yet there is limited information about early colonisation and development of bacterial communities that constitute the oral microbiome.

Aim: The aim of this study was to determine the effect of exposure to breastmilk on assembly of the infant oral microbiome during the first 20 months of life.

Methods: The oral microbiomes of 39 infants, 13 who were never breastfed and 26 who were breastfed for more than 10 months, from the longitudinal VicGeneration birth cohort study, were determined at four ages.

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While the mortality rates for many cancers have decreased due to improved detection and treatments, that of pancreatic cancer remains stubbornly high. The microbiome is an important factor in the progression of many cancers. Greater understanding of the microbiome in pancreatic cancer patients, as well as its manipulation, may assist in diagnosis and treatment of this disease.

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Aim: Periodontitis is a site-specific, chronic disease treated by non-surgical debridement of subgingival plaque. We aimed to determine the microbiome of sites that did not respond to this treatment (NR) compared with paired good responding (GR) sites before and after treatment.

Materials And Methods: In a longitudinal cohort study, clinical parameters of disease and biological samples were taken prior to and 3 months after treatment.

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The human oral microbiome is becoming recognized as playing roles in health and disease well beyond the oral cavity over the lifetime of the individual. The oral microbiome is hypothesized to result from specific colonization events followed by a reproducible and ordered development of complex bacterial communities. Colonization events, proliferation, succession and subsequent community development are dependent on a range of host and environmental factors, most notably the neonate diet.

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causes candidiasis, particularly in immunocompromised patients. K12 (K12) is a probiotic isolated from a healthy oral cavity. The study aimed to determine the effect of K12 on aggregation, biofilm formation and dimorphism.

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Bacteriophages are viruses that specifically lyse bacteria. They have demonstrated potential in applications as antibacterial agents in medicine, agriculture, and environmental remediation. Due to the complex and dynamic nature of the oral microbiome, antibiotic treatment of chronic, polymicrobial oral diseases may lead to dysbiosis.

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Some cancer treatment failures have been attributed to the tumour microbiota, with implications that microbiota manipulation may improve treatment efficacy. While antibiotics have been used to control bacterial growth, their dysbiotic effects on the microbiome, failure to penetrate biofilms and decreased efficacy due to increasing antimicrobial resistance by bacteria, suggest alternatives are needed. Bacteriophages may provide a precise means for targeting oncobacteria whose relative abundance is increased in tumour tissue microbiomes.

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Introduction: Research has highlighted relationships between the micro-organisms that inhabit our gastrointestinal tract (oral and gut microbiota) with host mood and gastrointestinal functioning. Mental health disorders and functional gastrointestinal disorders co-occur at high rates, although the mechanisms underlying these associations remain unclear. The Bugs and Brains Study aims to investigate complex relationships between anxiety/depression and irritable bowel syndrome (IBS) in two ways.

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Concerns regarding increasing antibiotic resistance raise the question of the most appropriate oral antibiotic for empirical therapy in dentistry. The aim of this systematic review was to investigate the antibiotic choices and regimens used to manage acute dentoalveolar infections and their clinical outcomes. A systematic review was undertaken across three databases.

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Background:   and  are proteolytic periodontopathogens that co-localize in polymicrobial subgingival plaque biofilms, display  growth symbiosis and synergistic virulence in animal models of disease. These symbioses are underpinned by a range of metabolic interactions including cooperative hydrolysis of glycine-containing peptides to produce free glycine, which  uses as a major energy and carbon source.

Objective:  To characterize the  gene products essential for these interactions.

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Purpose: Depression and anxiety are highly prevalent disorders, whose significant burden is compounded by the presence of oral disease. Mental health disorders and oral health may be associated via changes to the oral microbiome, involving increased pro-inflammatory communication and cortisol in saliva. The present study provides the first culture-independent investigation of the oral microbiome considering depression and anxiety symptoms in adolescence, a critical age where these conditions begin to emerge and co-occur.

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Objective: To examine associations between childcare type and nutrition and oral health indicators.

Design: Cross-sectional data extracted from a longitudinal birth cohort. Parent-completed FFQ and questions regarding oral health and childcare use.

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Objectives: To assess the CAMBRA caries risk assessment tool (CRAT) in terms of its measurement properties: reliability, validity and responsiveness to change in caries estimates over time.

Methods: Secondary data from the VicGeneration (VicGen) birth cohort study were used. Caries risk status at child age18 months was compared against caries development at 36 and 48 months.

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Oral squamous cell carcinoma is associated with many known risk factors including tobacco smoking, chronic alcoholism, poor oral hygiene, unhealthy dietary habits and microbial infection. Previous studies have highlighted Candida albicans host tissue infection as a risk factor in the initiation and progression of oral cancer. C albicans invasion induces several cancerous hallmarks, such as activation of proto-oncogenes, induction of DNA damage and overexpression of inflammatory signalling pathways.

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Objectives: The aim of this birth cohort study was to identify concurrent associations between early childhood caries and putative risk and protective factors.

Methods: Data were collected in seven waves over five years. The study outcome measure, dmfs, was modelled in a set of sequential negative binomial regressions that introduced the variables in steps starting from health determinants most distal to the child and ending with the more proximal ones.

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