1,720,999 research outputs found
A commercial SnF2 toothpaste formulation reduces simulated human plaque biofilm in a dynamic typodont model
No full textAims: we present a dynamic typodont biofilm model (DTBM) incorporating 1) human dentition anatomy, 2) fluid flow over intermittently fluid bathed tooth surfaces and 3) an oxic headspace to allow aerobic and anaerobic niches to develop naturally, as a screening tool to assess the effect of stannous fluoride (SnF2) toothpaste against a simulated human plaque biofilm (SPB). Methods and results: first, hydroxyapatite (HA) coupons were inoculated with human saliva/plaque and cultured at 37oC under air. Selected species representative of common commensal and anaerobic pathogens were quantified for relative abundance changes over 4d by PCR densitometry to confirm the culture conditions allowed the proliferation of these species. A continuous culture DTBM reactor on a rocker table was inoculated with saliva/plaque and incubated at 37°C for 24h. Tooth shear stress was estimated by particle tracking. A SnF2 toothpaste solution, or a sham rise was administered twice daily for 3d to mimic routine oral hygiene. SPB biomass was assessed by total bacterial DNA and methylene blue (MB) staining. Early colonizer aerobes and late colonizer anaerobes species were detected in the HA and DTBM, and the trends in changing abundance were consistent with those seen clinically. Conclusions: treatment with the SnF2 solution showed significant reductions of 53.05% and 54.4% in the SPB by MB staining and DNA, respectively. Significance and impact of study: The model has potential for assessing dentition anatomy and fluid flow on the efficacy of antimicrobial efficacy against localized SPB and may be amenable to the plaque index clinical evaluation
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Sources of the Placental Microbiome in Full-term, Pre-term, and Pre-eclampsia
Full text linkHealth Sciences: 3rd Place (The Ohio State University Edward F. Hayes Graduate Research Forum)Objective: In the US, pre-term birth affects 1 in 9 babies and pre-eclampsia occurs in 3-8% of pregnancies. While the cause of pre-eclampsia is unknown, placental dysfunction caused by angiogenic imbalances and inflammatory disturbances plays a role. Previous research in the lab has shown that disturbances to the microbiome may also cause an upregulation in inflammatory markers. Therefore, we thought that dysbiosis in the microbiome may be a factor in inflammation that leads to adverse pregnancy outcomes. We aimed to investigate whether the oral microbiome has a role in contributing to pre-term delivery or pre-eclampsia. Methods: Saliva, plaque, serum, and placental samples were collected from 130 women (45 healthy, 36 with pre-eclampsia, and 49 who delivered pre-term). DNA was isolated and underwent whole genome sequencing. Taxonomy was assigned using Kraken against the Human Oral Microbiome Database (HOMD). Multiple bioinformatic tools were used to analyze the sequencing data: Prodigal, DIAMOND, and MEGAN were used to read, translate, and determine gene identity and function as indicated in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, the Comprehensive Antibiotic Resistance Database (CARD), and the Virulence Factor Database (VFDB). SourceTracker quantified the contributions of the salivary, plaque, and serum biomes to the placental biome. ALDEx2 determined differential species abundance and sparce partial least squares discriminant analysis (sPLS-DA) revealed the primary drivers of separation seen within the placental samples. Results: All placental samples in the study demonstrated the presence of a microbiome and the composition of the microbiome did not differ between mode of delivery, vaginal or c-section (p-value=0.973, Aitchison distance, PERMANOVA). However, placental samples demonstrated significant beta dispersion in all three groups functionally. This was not observed in sequences of salivary or serum origin. Principle component analysis of Aitchison distance revealed clustering of the placental microbiome based on pregnancy outcome, both taxonomically and functionally (p-value=0.001 for both, PERMANOVA). sPLS-DA demonstrated that placental levels of B. subtilis was an indicator of a healthy pregnancy outcome while L. crispatus indicated pre-term, and C. matruchotii indicated pre-eclampsia. Many metabolism-associated genes, such as type I restriction enzyme and transcription-repair coupling factor, and a disease associated gene, GTP-binding protein LepA, were also indicators of pre-eclampsia. SourceTracker revealed that saliva was the predominant source of microorganisms in serum in all three groups. SourceTracker also revealed serum to be the predominant source of the placental biome. In mothers with pre-eclampsia, saliva was an additional source of the placenta's biome. Conclusion: The oral microbiome is a source of the placental microbiome and the translocation of certain oral species to the placenta via the serum is associated with pre-term delivery and pre-eclampsia. Promoting healthy oral bacteria in a mother may therefore help reduce her risk of adverse pregnancy complications. Little things like taking care of mom's oral health have a big impact on the mother's health as well as her child's. In subsequent studies, we would like to determine whether the gut microbiome also plays a role as microorganisms may be able to translocate if the woman is suffering from "leaky gut" syndrome as other labs have shown that early onset pre-eclampsia is associated with gut microbiome changes.A three-year embargo was granted for this item
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Oral Health and JUUL: A Toxic Relationship
No full textPoster Division: Health Sciences: 2nd Place (The Ohio State University Edward F. Hayes Graduate Research Forum)A five-year embargo was granted for this item
Impact of maternal gestational exposures on development of the infant oral microbiome
No full textPoster Division: Health Sciences: 1st Place (The Ohio State University Edward F. Hayes Graduate Research Forum)A five-year embargo was granted for this item
Contribution of Ethnicity to Subgingival Microbial Colonization
Full text linkIntroduction: Although it is known that the gingival sulcus contains a complex microbial ecosystem, the role of host-associated colonization factors, especially ethnicity, in determining the composition of this community is not known. Open-ended molecular approaches are comprehensive tools that allow us to compare profiles of microbial communities with several as-yet-uncultivated organisms. Objective: To compare the subgingival microbial profiles of periodontally healthy subjects belonging to four different ethnicities. Methods: 55 periodontally healthy subjects of Caucasian (n=17), African-American (n=14), Hispanic (n=17), and Chinese (n=17) ethnicities were recruited. All subjects were over age 18 without history of systemic disease, pregnancy, and recent or prophylactic antibiotic use. Ethnicity information and subgingival plaque samples were collected. 16S rRNA genes were amplified using polymerase chain reaction with fluorescently labeled broad-range primers and digested using MspI restriction enzyme. Terminal Restriction Fragment Length Polymorphism Analysis (t-RFLP) was used to examine microbial profiles. Non-parametric tests were used for between group comparisons. Results: A statistically significant difference was found in the total peaks measured between African-Americans and Chinese (p=0.0165), African-American and Latino (p=0.0001), Caucasian and Chinese (p=0.0468), and Caucasian and Latino (p=0.0005,Kruskal-Wallis analysis). Conclusions: There is an association between ethnic preference and the bacterial composition of the health- associated subgingival plaque. However, the effect of shared environment remains to be investigated.This research was supported by the Rudy Melfi undergraduate research fellowship to Matthew Mason through the OSU College of DentistryNo embarg
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Generalized Aggressive Periodontitis - A Periodontal Chimera
No full textHealth Sciences: 1st Place (The Ohio State University Edward F. Hayes Graduate Research Forum)Objectives: Periodontitis is a disease of the surrounding tissues of the tooth (periodontium) in which the destruction leads to weakening of the tooth support and eventual tooth loss. Approximately 46% of adults in the US suffer from this disease.1 The current classification of periodontal diseases and conditions recognizes 3 forms of periodontitis: Chronic periodontitis (CP), Localized Aggressive Periodontitis (LAP), and Generalized Aggressive Periodontitis (GAP). All three are inflammatory conditions that are microbial in nature. GAP is considered the most destructive of the three conditions due to its rapid destruction of the periodontium and its wide distribution in the mouth. Previous close-ended approaches to examine the bacterial constituents of the 3 diseases were equivocal, however, the consensus is that CP and GAP are considered polymicrobial in nature, while LAP is attributed to a mono-infection of the bacterial species Aggregatibacter actinomycetemcomitans.2 Since evidence is emerging that taxonomically distinct periodontal biofilms are functionally congruent, the present investigation sought to characterize the functional potential within the subgingival bacteria of CP, GAP and LAP. Methods: Subgingival plaque samples were collected from deep and shallow sites of 25 patients with CP, 17 with GAP, and 17 with LAP. Whole-genome shotgun DNA sequencing was used to characterize the functions encoded in these microbial communities. Sequences were analyzed using the MG-RAST pipeline for subsystem classification, and Kraken for taxonomic identification. Organismal diversity and functional abundances were compared between groups using dissimilarity indices, differential abundance metrics and network analysis. Results: 11.5 million sequences per sample contributed to 5973 functionally annotated genes. Principal coordinate analysis revealed distinct clustering of the three diseases based on community membership, structure and functional potential (p<0.05, ANOSIM). GAP separated the distances between LAP and CP, concordant with concept of a mixed infection of the two diseases. GAP and CP had similar functions of fermentation, phage transfer, while GAP and LAP had similar virulence factors. Taxonomic analysis revealed the polymicrobial nature of all three conditions. Network analysis showed similar inter-bacterial interaction networks between GAP and LAP, with similar membership of Treponema denticola, Filifactor alocis, Tannerella forsythia and Porphyromonadaceae Spp. Implications: This is the first time that the three disease entities are shown to exist as a continuum rather than discrete disease entities. This paradigm shift in has major implications on the classification of disease. That is, the aggressive but localized nature of LAP is globalized to the entire periodontal tissues by the superimposition of CP. Moreover, these findings cast doubt on current empirical treatment protocols for GAP that follow closely the protocols made for LAP. Finally, the breadth of the microbial members in LAP extend beyond the single bacteria species which greatly expands our understanding of the disease.A five-year embargo was granted for this item
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