Publications by authors named "Roger Junges"

Saliva has emerged as a promising diagnostic fluid for viral infections, enabling the direct analysis of viral genetic material and the detection of infection markers such as proteins, metabolites, microRNAs, and immunoglobulins. This comprehensive review aimed to explore the use of saliva as a diagnostic tool for viral infections, emphasizing its advantages and limitations. Saliva stands out due to its simplicity and safety in collection, along with the convenience of self-collection without the need for healthcare supervision, while potentially being comparable to urine and blood in terms of effectiveness.

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Article Synopsis
  • Dentists play a crucial role in tackling the antimicrobial resistance (AMR) crisis, but little is known about dental students' perceptions of this issue in the Asia-Pacific region, which is crucial for AMR development and spread.
  • A survey conducted across 15 dental schools in Australia, Sri Lanka, Japan, and Vietnam found that dental students had a high awareness of AMR (mean score 8.09), but the confidence to prescribe antibiotics was lower (mean score 6.01), with many feeling pressured to prescribe due to patient demand or time constraints.
  • Final-year dental students involved in research had a higher priority for addressing AMR compared to their non-research peers, indicating the
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Background: Torquetenovirus (TTV) is a small DNA virus constituting the human virome. High levels of TTV-DNA have been shown to be associated with immunosuppression and inflammatory chronic disorders.

Aim: To assess the possible association between the salivary viral load of TTV-DNA in patients hospitalised due to COVID-19 and disease severity.

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Antifungal agents are widely used to specifically eliminate infections by fungal pathogens. However, the specificity of antifungal agents has been challenged by a few studies demonstrating antibacterial inhibitory effects against and species. Here, we evaluated for the first time the potential effect of fluconazole, the most clinically used antifungal agent, on a human oral microbiota biofilm model.

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Introduction: Low microbial biomass and high human DNA content in nasopharyngeal aspirate samples hinder comprehensive characterization of microbiota and resistome. We obtained samples from premature infants, a group with increased risk of developing respiratory disorders and infections, and consequently frequent exposure to antibiotics. Our aim was to devise an optimal protocol for handling nasopharyngeal aspirate samples from premature infants, focusing on host DNA depletion and microbiome and resistome characterization.

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The collateral impact of antibiotics on the microbiome has attained increasing attention. However, the ecological consequences of long-term antibiotic exposure on the gut microbiome, including antibiotic resistance, are still limited. Here, we investigated long-term exposure effects to amoxicillin on the human gut microbiome and resistome.

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Background: The antimicrobial resistance (AMR) crisis is a major global threat and one of its biggest drivers is the overuse of antibiotics in humans. Dentists are responsible for 5-10% antibiotic prescriptions worldwide and recent data suggest that knowledge and prescribing practices need improvement.

Methods: A cross-sectional web-survey was sent to dental students from six universities in Norway, Canada, and Brazil.

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Selective markers employed in classical mutagenesis methods using natural genetic transformation can affect gene expression, risk phenotypic effects, and accumulate as unwanted genes during successive mutagenesis cycles. In this chapter, we present a protocol for markerless genome editing in Streptococcus mutans and Streptococcus pneumoniae achieved with an efficient method for natural transformation. High yields of transformants are obtained by combining the unimodal state of competence developed after treatment of S.

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Background: COVID-19 is a disease affecting various human organs and systems, in which the virus seeks to interact with angiotensin-converting enzyme 2 receptors. These receptors are present in the oral cavity, but the direct relationship between such an interaction and possible oral manifestations of COVID-19 is still unclear.

Aim: The present study evaluated oral manifestations in a cohort of COVID-19 patients during the period of hospitalisation.

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The study of resistomes using whole metagenomic sequencing enables high-throughput identification of resistance genes in complex microbial communities, such as the human microbiome. Over recent years, sophisticated and diverse pipelines have been established to facilitate raw data processing and annotation. Despite the progress, there are no easy-to-use tools for comprehensive visual, statistical and functional analysis of resistome data.

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The mitis group of streptococci comprises species that are common colonizers of the naso-oral-pharyngeal tract of humans. and are close relatives and share ~60-80% of orthologous genes, but still present striking differences in pathogenic potential toward the human host. has long been recognized as a reservoir of antibiotic resistance genes for , as well as a source for capsule polysaccharide variation, leading to resistance and vaccine escape.

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Natural transformation is regarded as an important mechanism in bacteria that allows for adaptation to different environmental stressors by ensuring genome plasticity. Since the discovery of this phenomenon in , remarkable progress has been made in the understanding of the molecular mechanisms and pathways coordinating this process. Recently, the advent of high-throughput sequencing allows the posing of questions that address the system at a larger scale but also allow for the creation of high-resolution maps of transcription.

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Objectives: The aims of this study were to explore the shape of the relationship of income and education with periodontal health, and to assess the interactions between them and race/ethnicity.

Method: Individual level data from the Brazilian National Oral Health Survey in 2010 (Pesquisa Nacional de Saúde Bucal-SB Brasil 2010) were obtained for 9,779 subjects. Relations between per capita income and education with periodontal health were smoothed using Locally Weighted Scatter-plot Smoother (Lowess) technique.

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Homologous recombination in the genetic transformation model organism Streptococcus pneumoniae is thought to be important in the adaptation and evolution of this pathogen. While competent pneumococci are able to scavenge DNA added to laboratory cultures, large-scale transfers of multiple kb are rare under these conditions. We used whole genome sequencing (WGS) to map transfers in recombinants arising from contact of competent cells with non-competent 'target' cells, using strains with known genomes, distinguished by a total of ~16,000 SNPs.

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Despite vaccines, kills more than a million people yearly. Thus, understanding how pneumococci transition from commensals to pathogens is particularly relevant. Quorum sensing regulates collective behaviors and thus represents a potential driver of commensal-to-pathogen transitions.

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Natural transformation is used by bacteria to take up DNA from their surroundings and incorporate it into their genomes. Streptococci do so during a transient period of competence, triggered by pheromones that they produce, secrete and sense under conditions influenced by the environment. In Streptococcus mutans, Streptococcus suis, and species of the bovis, salivarius and pyogenic groups of streptococci, the pheromone XIP is sensed by the intra-cellular regulator ComR, that in turn activates the transcription of comS, encoding the XIP precursor, and of sigX, encoding the only known alternative sigma factor in streptococci.

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The aim of this study was to assess the accuracy of clinical diagnosis for lip lesions based on sensitivity and specificity. The retrospective analysis focused on the detection of lesions caused by potentially malignant disorders (PMDs) and malignant lesions (n = 1195). All cases were classified as benign, PMD, and malignant lesions.

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Selective markers employed in classical mutagenesis methods using natural genetic transformation can affect gene expression, risk phenotypic effects, and accumulate as unwanted genes during successive mutagenesis cycles. In this chapter, we present a protocol for markerless genome editing in Streptococcus mutans and Streptococcus pneumoniae achieved with an efficient method for natural transformation. High yields of transformants are obtained by combining the unimodal state of competence developed after treatment of S.

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The discovery that Streptococcus pneumoniae uses a competence-stimulating peptide (CSP) to induce competence for natural transformation, and that other species of the mitis and the anginosus streptococcal groups use a similar system, has expanded the tools to explore gene function and regulatory pathways in streptococci. Two other classes of pheromones have been discovered since then, comprising the bacteriocin-inducing peptide class found in Streptococcus mutans (also named CSP, although different from the former) and the SigX-inducing peptides (XIP), in the mutans, salivarius, bovis, and pyogenes groups of streptococci. The three classes of peptide pheromones can be ordered from peptide synthesis services at affordable prices, and used in transformation assays to obtain competent cultures consistently at levels usually higher than those achieved during spontaneous competence.

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Objective: Streptococcus mitis is a predominant oral colonizer, but difficulties in genetic manipulation of this species have hampered our understanding of the mechanisms it uses for colonization of oral surfaces. The aim of this study was to reveal optimal conditions for natural genetic transformation in S. mitis and illustrate its application in direct genome editing.

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Purpose: To evaluate elementary schoolteachers' knowledge and decision making regarding dental trauma in Porto Alegre, Brazil.

Materials And Methods: A questionnaire-based survey was conducted among elementary schoolteachers (n=442). Questions encompassed sociodemographic characteristics and decision making regarding dental trauma.

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The aim of this study was to measure the publication rate of editorial board members in their board journals and to evaluate associated variables. We evaluated the ten highest-ranked journals according to the 5-year impact factor under 'Dentistry, Oral Surgery & Medicine' subject category for 2010, 2011, and 2012. All original research papers with at least one member of the editorial board as author were counted.

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Background And Objective: The number of elderly living in long-term care (LTC) institutions has been increasing in many countries. The objective of this study was to evaluate the caregivers' attitudes and considerations regarding oral health and oral health practices in an LTC institution in Porto Alegre, Brazil.

Materials And Methods: The population comprised the caregivers (n = 27) at an LTC in Porto Alegre, Brazil.

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Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) are critical for tissue remodeling during wound repair. Psychological stress has been found to impair wound healing in humans and animals. The objective of this study was to assess MMP and TIMP gene expression during stress-impaired healing.

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