Resolvin E1 Reverses Experimental Periodontitis and Dysbiosis

Periodontitis is a biofilm-induced inflammatory disease characterized by dysbiosis of the commensal periodontal microbiota. It is unclear how natural regulation of inflammation affects the periodontal biofilm. Promoters of active resolution of inflammation including Resolvin E1 (RvE1) effectively treat inflammatory periodontitis in animal models. The goals of this study were 1) to compare periodontal tissue gene expression in different clinical conditions, 2) to determine the impact of local inflammation on the composition of subgingival bacteria, and 3) to understand how inflammation impacts these changes. Two clinically-relevant experiments were performed in rats: prevention and treatment of ligature-induced periodontitis with RvE1 topical treatment. The gingival transcriptome was evaluated by RNA-seq sequencing of mRNA. The composition of the subgingival microbiota was characterized by 16S rDNA sequencing. Periodontitis was assessed by bone morphometric measurements and histomorphometry of block sections. H&E and, tartrate resistant acid phosphatase staining were used to characterize and quantify inflammatory changes. RvE1 treatment prevented bone loss in ligature induced periodontitis. Osteoclast density and inflammatory cell infiltration in the RvE1 groups were lower than those in the placebo group. RvE1 treatment reduced expression of inflammation-related genes returning the expression profile to one more similar to health. Treatment of established periodontitis with RvE1 reversed bone loss, reversed inflammatory gene expression and reduced osteoclast density. Assessment of the rat subgingival microbiota after RvE1 treatment revealed marked changes in both prevention and treatment experiments. The data suggest that modulation of local inflammation has a major role in shaping the composition of the subgingival microbiota

Microbial Ecosystem Analysis in Root Canal Infections Refractory to Endodontic Treatment

Introduction To combine Multiple Displacement Amplification (MDA) and checkerboard DNA–DNA hybridization to qualitatively and quantitatively evaluate the microbiota present in infections refractory to endodontic treatment. Methods The subjects of this study were 40 patients presenting periapical lesions refractory to endodontic treatment. Samples were taken by scraping or filing root canal walls with a #10 K-type hand file. Sample DNA was amplified by MDA, and the levels of 107 bacterial taxa were analyzed by checkerboard DNA–DNA hybridization. The taxa were divided into three distinct microbial populations, depending on their mean proportion in samples (% DNA probe counts ± SEM), as follows: dominant (≥3.0%), sub-dominant (\u3e1.6 to 3.0%) and residual (≤1.6%) populations. The significance of differences was determined using the Mann-Whitney test. Results The taxa present with the highest mean proportions (constituting the dominant population) were Corynebacterium diphtheriae (8.03±0.98), Porphyromonas gingivalis (5.42±2.09), Streptococcus sobrinus (5.33±0.69), and Stenotrophomonas maltophilia (4.72±1.73). Among the sub-dominant population were Eubacterium saphenum (3.85±1.06), Helicobacter pylori (3.16±0.62), Dialister pneumosintes (3.12±1.1), Clostridium difficile (2.74±0.41), Enterobacter agglomerans (2.64±0.54), Salmonella enterica (2.51±0.52), Mobiluncus mulieris (2.44±0.6), and Klebsiella oxytoca (2.32±0.66). In the population of bacteria present at the lowest mean proportions (the residual population), Bacteroides ureolyticus (0.04±0.01), Haemophilus influenzae (0.04±0.02), and Prevotella oris (0.01±0.01) were found at the lowest mean proportions. Enterococcus faecalis was detected in the residual population (0.52±0.26). Conclusion The microbial climax community in teeth refractory to endodontic treatment not only harbor medically important species, but also contains distinct microbial consortia present with different population levels

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Análise microbiológica de infecções endodônticas utilizando a associação das técnicas do Multiple Displacement Amplification (MDA) e da Hibridização DNA-DNA (Checkerboard)

Exportado OPUSMade available in DSpace on 2019-08-11T05:07:02Z (GMT). No. of bitstreams: 1 luciana_carla_neves_de_brito_mestrado.pdf: 247273 bytes, checksum: 1fa8f4abbc897f81ca7770fd5246173f (MD5) Previous issue date: 7A técnica do Multiple Displacement Amplification (MDA) vem sendo utilizado para amplificar uniformemente o genoma bacteriano presente em pequenas amostras, fornecendo grandes melhorias nas análises moleculares. O propósito desta pesquisa foi associar o MDA e a hibridização DNA-DNA (checkerboard) para examinar a microbiota de infecções endodônticas. Sessenta e seis amostras foram coletadas de infecções endodônticas. As amostras não amplificadas e aquelas amplificadas pelo MDA foram analisadas pelo checkerboard para a determinação dos níveis e proporções de 77 taxas bacterianas. Computaram-se a contagem, percentagem do total de DNA e percentagem de dentes colonizados para cada espécie em amostras amplificadas e não amplificadas. As diferenças significantes para cada espécie entre as amostras amplificadas e não amplificadas foram determinadas utilizando-se o teste de Wilcoxon e ajustado para comparações múltiplas. A quantidade média de DNA presente nas amostras clínicas variou de 6,80 (± 5,2) ng sem amplificação a 6,26 (± 1,73) ìg após a utilização do MDA. Setenta das 77 sondas de DNA hibridizaram com uma ou mais das amostras não amplificadas, enquanto todas as sondas hibridizaram com no mínimo uma amostra após a amplificação. As espécies mais comumente detectadas no nível > 104 células bacterianas, nas amostras amplificadas e não amplificadas, foram Prevotella tannerae e Acinetobacter baumannii numa freqüência que variou de 89-100% das amostras. O número médio (± SEM) de espécies nas contagens >104 células bacterianas, nas amostras amplificadas, foi de 51,2 ± 2,2 e, nas não amplificadas, foi de 14,5 ± 1,7. A combinação do MDA e da hibridização DNA-DNA (checkerboard) demonstrou a presença de uma grande variedade de espécies bacterianas nas amostras endodônticas demonstrando sua utilidade naqueles estudos que avaliam a microbiota presente nas infecções endodônticas.Multiple Displacement Amplification (MDA) has been used to uniformly amplify bacterial genomes present in small samples, providing abundant targets for molecular analysis. The purpose of this investigation was to combine MDA and checkerboard DNA-DNA hybridization to examine the microbiota of endodontic infections. 66 samples were collected from teeth with endodontic infections. Non-amplified and MDA amplified samples were analyzed by checkerboard DNA-DNA hybridization for levels and proportions of 77 bacterial taxa. Counts, % DNA probe counts and % of teeth colonized for each species in amplified and non-amplified samples were computed. Significance of differences for each species between amplified and non- amplified samples was determined using the Wilcoxon signed ranks test and adjusted for multiple comparisons. The average amount of DNA present in clinical samples ranged from 6.80 (± 5.2) ng before to 6.26 (± 1.73) ìg after MDA. 70 of the 77 DNA probes hybridized with one or more of the non-amplified samples, while all probes hybridized with at least one sample after amplification. Most commonly detected species at levels > 104 in both amplified and non-amplified samples were Prevotella tannerae and Acinetobacter baumannii at frequencies ranging from 89-100% of samples. The mean number (± SEM) of species at counts >104 in amplified samples was 51.2 ± 2.2 and in non-amplified samples was 14.5 ± 1.7. The combination of MDA and checkerboard DNA-DNA hybridization demonstrated the presence of wide range of bacterial species in endodontic samples and could facilitate studies evaluating the microbiota of endodontic infections

Análise epidemiológica, microbiológica e resposta imune periapical em pacientes HIV positivos e negativos portadores de infecções endodônticas

Exportado OPUSMade available in DSpace on 2019-08-14T07:56:27Z (GMT). No. of bitstreams: 1 tese_doutorado_luciana_carla_neves_de_brito.pdf: 1639849 bytes, checksum: 1b5a40bc294b8b9db7148aeccc72481e (MD5) Previous issue date: 22As patologias pulpo-periapicais abrangem muitas áreas do conhecimento, tais quais a epidemiologia, microbiologia e imunologia. Muito estudadas em humanos e animais, pouco foi pesquisado sobre a interferência da síndrome da imunodeficiência adquirida humana sobre essas alterações. Este estudo analisou a necessidade de tratamento endodôntico em uma população HIV-positiva, e correlacionou esse achado com os dados pessoais e sistêmicos desses indivíduos. Aqueles que apresentavam necessidade de tratamento endodôntico tiveram seus canais radiculares analisados quanto ao perfil microbiológico e imunológico. Pacientes HIV negativos foram também avaliados para que se confrontassem os dados. Avaliou-se a presença de 107 espécies microbianas utilizando-se a associação das técnicas do Multiple Displacement Amplification (MDA) e da Hibridização DNA-DNA Checkerboard. Utilizando-se o Real Time PCR, avaliou-se a expressão gênica de linfócitos TCD4+CD28+ e TCD8+, citocinas e quimiocinas: TNF-, IL-1, IL-10, IL-17A, RANKL, IFN-, CCL2, CCL4, CCL5, CXCR4, CCR5. As amostras foram coletadas em dois momentos distintos, imediatamente após os procedimentos de limpeza e formatação e 7 dias após. Pode-se observar que a maioria dos indivíduos HIV-positivos eram mulheres, 14% apresentavam necessidade de tratamento endodôntico, 79.2% estavam sob HAART, e que existia uma correlação positiva entre a necessidade de tratamento endodôntico e uma baixa contagem de células TCD4+. Detectou-se uma média de espécies por canal de 22.6 (± 1.4) e 21.3 (± 2.0) nos indivíduos HIV- e HIV+ respectivamente. D. pneumosintes, H. pylori e S. constellatus foram detectadas em maior proporção nos indivíduos HIV+. A expressão gênica de células TCD4+CD28+ e TCD8+ aumentou após a redução do conteúdo microbiano intracanal em ambos os indivíduos, HIV-positivo e negativo. Observou-se que nos indivíduos HIV-negativos houve uma redução na expressão de mediadores pró-inflamatórios com a redução do conteúdo microbiano, enquanto que nos indivíduos HIV-positivos houve um aumento na expressão desses mediadores no mesmo período, que correlacionou-se com um aumento na expressão da IL-10 nos indivíduos HIV-negativos e, do CXCR4 nos indivíduos HIV-positivos. Pode-se concluir que: a) apesar da relação positiva entre a necessidade de intervenção endodôntica e a baixa contagem de células TCD4+, tal fenômeno se deve provavelmente a uma baixa aderência ao HAART; b) ao se comparar a microbiota de indivíduos HIV-positivos e negativos confirmou-se que a infeção é polimicrobiana com algumas espécies de importância médica dominando os SCR dos indivíduos HIV-positivos; c) a expressão dos marcadores celulares TCD4+CD28+ e CD8+, em ambos os indivíduos, HIV-positivos e negativos, é afetada pela presença de estímulos microbianos nos SCR; d) a expressão gênica de citocinas e quimiocinas demonstrou que a resposta pró-inflamatória nos pacientes HIV-positivos acontece mais tardiamente quando comparada àquela observada nos indivíduos HIV-negativos.Pulpo-periapical pathologies cover many areas of knowledge, including epidemiology, microbiology and immunology. Even though they have been widely investigated in humans and animals, there is a gap in knowledge regarding the role of the human acquired immunodeficiency syndrome on these pathologies. The present study evaluated the need for endodontic treatment in an HIV-positive population and assessed its correlation with systemic and personal data of those individuals. Subjects that needed endodontic treatment had the root canals of those teeth analyzed for their microbiological and immunological profile. HIV-negative individuals (that needed endodontic therapy) were selected as controls for comparison. We evaluated the presence of 107 microbial species by combining the Multiple Displacement Amplification (MDA) technique and the checkerboard DNA-DNA hybridization technique. Using Real Time PCR, we evaluated the gene expression of lymphocytes TCD4+CD28+ and TCD8+, cytokines and chemokines: TNF-, IL-1, IL-10, IL-17A, IFN-, CCL2, RANKL, CCL4, CCL5, CXCR4, and CCR5. Samples were collected at two times points, immediately after cleaning and shaping the root canal system and 7 days later. In the HIV-positive group, it was observed that the majority individuals were females, that 14% of the subjects needed endodontic treatment and that 79.2% of the HIV positive subjects were under the HAART regimen. There was a positive correlation between the need for endodontic treatment and a low CD4 + T-cells count. There were, in average, 22.6 (± 1.4) and 21.3 (± 2.0) species per root canal in HIV-and HIV + respectively (mean±SD). D. pneumosintes, H. pylori and S. constellatus were the most abundant bacterial species among HIV positive individuals. The geneexpression of TCD4 CD28 cells and TCD8 increased after the reduction of intracanal microbial content in both groups (HIV-positive and HIV-negative). It was observed that in HIV-negative individuals the local expression of pro-inflammatory mediators was downregulated after root canal instrumentation. Conversely, in HIV-positive individuals the expression of these mediators was upregulated in the same time point, which paralleled with an upregulation of IL-10 in HIV-negative and CXCR4 in HIV-positive individuals. It can be concluded that: a) despite the positive relationship between the need for endodontic treatment and low counts of CD4+ T cells, this phenomenon is probably due to a low adherence to HAART regimen, b) when comparing the root canal microbiota of HIV-positive and negative individuals it was observed that these infections are polymicrobial and include medically important bacterial species, which were commonly found in the SCR of HIV-positive subjects; c) the expression of TCD4+CD28+ and TCD8+ cell markers in both groups (HIV-positive and negative) seems to be affected by the presence of microbial stimuli inside SCR; d) the (local) gene expression of cytokines and chemokines showed that the pro-inflammatory response in HIV-positive occurs later, when compared to that observed in HIV-negative subjects