The response of dual-species bacterial biofilm to 2% and 5% NaOCl mixed with etidronic acid:A laboratory real-time evaluation using optical coherence tomography

Aim: The addition of etidronic acid (HEDP) to sodium hypochlorite (NaOCl) could increase the antibiofilm potency of the irrigant, whilst maintaining the benefits of continuous chelation. Studies conducted so far have shown that mixing HEDP with NaOCl solutions of relatively low concentration does not compromise the antibiofilm efficacy of the irrigant. However, the working lifespan of NaOCl may decrease resulting in a reduction of its antibiofilm efficacy over time (efficiency). In this regard, continuous irrigant replenishment needs to be examined. This study investigated the response of a dual-species biofilm when challenged with 2% and 5% NaOCl mixed with HEDP for a prolonged timespan and under steady laminar flow. Methodology: Dual-species biofilms comprised of Streptococcus oralis J22 and Actinomyces naeslundii T14V-J1 were grown on human dentine discs in a constant depth film fermenter (CDFF) for 96 h. Biofilms were treated with 2% and 5% NaOCl, alone or mixed with HEDP. Irrigants were applied under steady laminar flow for 8 min. Biofilm response was evaluated by means of optical coherence tomography (OCT). Biofilm removal, biofilm disruption, rate of biofilm loss and disruption as well as bubble formation were assessed. One-way anova, Wilcoxon's signed-rank test and Kruskal–Wallis H test were performed for statistical analysis of the data. The level of significance was set at a ≤.05. Results: Increasing NaOCl concentration resulted in increased biofilm removal and disruption, higher rate of biofilm loss and disruption and increased bubble formation. Mixing HEDP with NaOCl caused a delay in the antibiofilm action of the latter, without compromising its antibiofilm efficacy. Conclusions: NaOCl concentration dictates the biofilm response irrespective of the presence of HEDP. The addition of HEDP resulted in a delay in the antibiofilm action of NaOCl. This delay affects the efficiency, but not the efficacy of the irrigant over time

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

Análise em micro-CT e microscopia eletrônica de varredura de novos instrumentos na desobturação e limpeza de canais achatados

The aim of this study was to evaluate the efficacy of heat-treated nickel-titanium reciprocating instruments and complementary techniques in retreatment of flattened canals. Material and methods: Twenty-six mandibular incisors were prepared up to size 25/.08 rotary file and filled using the single-cone technique. Subsequently, the teeth were divided into 3 groups (n=12) according to retreatment procedures: Reciproc Blue: R25 and R40; ProDesign R: PDR 25/.06 and PDR 35/.05; WaveOne Gold: WOG Primary and WOG Medium. The apically extruded material was collected in microtubes and the volume (mm³) was measured by Micro-CT. After this, the specimens received complementary cleaning with XP-Endo Shaper, PUI and 60° oscillatory instrumentation with #30 Hedströem file. Micro-CT scans were performed before and after removing filling material. After quantification of the volume of remaining filling material, the teeth were sectioned and scanning electron microscopy (SEM) images of the cervical, middle and apical thirds were obtained with a 700X magnification, and evaluated by scores based on the amount of filling material in the surface of dentine walls. Results: No reciprocating instrument promoted complete removal of filling material. All systems showed extrusion, however, WOG25 presented the higher extrusion of material (P .05). Conclusions: The reciprocating instruments studied did not promote complete removal of root canal filling materials. XP-Endo Shaper, used as a complementary instrument in retreatment, improved removal of filling material.O objetivo deste estudo foi avaliar a eficácia de instrumentos reciprocantes em níquel-titânio tratados termicamente e métodos complementares no retratamento de dentes com raízes achatadas. Materiais e métodos: Trinta e seis incisivos inferiores foram preparados com instrumentos rotatórios até o diâmetro 25./08 e obturados pela técnica do cone único. Em seguida, os dentes foram divididos em 3 grupos (n=12) de acordo com os sistemas utilizados para desobturação no retratamento: Reciproc Blue: R25 e R40; ProDesign R: PDR 25./06 e PDR 35/.05; WaveOne Gold: WOG Primary e WOG Medium. O material extruído apicalmente foi coletado em microtubos e o volume (mm³) foi mensurado com Micro-CT. Na sequência, os espécimes receberam limpeza complementar com XP-Endo Shaper ou com irrigação passiva ultrassônica (PUI) ou com instrumentação com lima #30 Hedströem em movimento oscilatório. Escaneamentos em Micro-CT foram realizados antes e após a remoção do material obturador. Após quantificação do volume de remanescente de material obturador, os dentes foram seccionados e imagens com microscópio eletrônico de varredura (MEV), dos terços cervical, médio e apical, foram obtidas com aumento de 700X, e avaliadas através de escores baseados na quantidade de material obturador remanescente nas paredes dentinárias. Resultados: Nenhum instrumento reciprocante promoveu remoção completa do material obturador. Todos os sistemas demonstraram extrusão, no entanto, WOG25 proporcionou maior extrusão (P.05). Os instrumentos reciprocantes estudados não promoveram a remoção completa do material obturador. XP-Shaper, utilizado como instrumento complementar no retratamento, aumentou a remoção de material obturador

Análise de diferentes irrigantes e protocolos de irrigação na limpeza, estrutura dentinária e ação antibiofilme

The aim of the first study was to investigate the biofilm response of two bacterial species after irrigation with 2% and 5% NaOCl mixed with HEDP for a prolonged period and under continuous flow. The increase in NaOCl concentration resulted in increased removal and disruption of the biofilm, as well as increased bubble formation. Association with HEDP caused a delay in the action of the hypochlorite, but without compromising the efficacy of the solution. In the second study, the influence of ethylenediaminetetraacetic acid (EDTA) pH on smear layer removal, effects on dentin structure, and antimicrobial action was analyzed. Regarding the removal of smear layer, there was no statistically significant difference between 17% EDTA pH5, pH7, and pH10. With respect to demineralization, acidified EDTA caused a higher and faster increase in the amide II/phosphate ratio. EDTA pH 7 showed a significant antimicrobial action and, in relation to its effect on the dentin structure, after irrigation with NaOCl, the amide II/phosphate ratio returned to the proportion close to the natural one. In the third study, the effect of different agitation protocols of the 2.5% NaOCl irrigating solution, associated or not with HEDP, on temperature was analyzed. Teeth were divided into 4 groups: G1 (NaOCl+Passive Ultrasonic Irrigation (PUI)), G2 (NaOCl/HEDP + PUI), G3 (NaOCl + Easy Clean (EC)) and G4 (NaOCl/HEDP + EC). At the end of the activation, the temperature (t) was measured and compared with t. initial. The cleaning of the dentinal tubules was analyzed using a Scanning Electron Microscope. PUI gently heated the different solutions, Easy Clean had the opposite effect. The association of NaOCl with chelating solutions promoted tubule cleaning.O objetivo do primeiro estudo foi investigar a resposta de biofilme de duas espécies bacterianas após irrigação com NaOCl 2% e 5% misturado com HEDP por um período prolongado e sob fluxo contínuo. O aumento da concentração do NaOCl resultou em aumento da remoção e disrupção do biofilme, além de maior formação de bolhas. Associação com HEDP causou atraso na ação do hipoclorito, mas sem comprometer a eficácia da solução. No segundo estudo foi analisada a influência do pH do ácido etilenodiamino tetra-acético (EDTA) na remoção da smear layer, efeitos na estrutura dentinária e ação antimicrobiana. Com relação a remoção da smear layer, não houve diferença estatisticamente significante entre EDTA 17% pH5, pH7 e pH10. Com relação a desmineralização, EDTA acidificado causou aumento da relação amida II/fosfato maior e mais rápido. EDTA pH 7 apresentou significativa ação antimicrobiana e, com relação ao seu efeito na estrutura dentinária, após irrigação com NaOCl, a razão amida II/fosfato retornou à proporção próxima ao natural. No terceiro estudo, foi analisado o efeito de diferentes protocolos de agitação da solução irrigadora NaOCl 2,5%, associada ou não ao HEDP, na temperatura. Os dentes foram divididos em 4 grupos: G1 (NaOCl+Irrigação Passiva Ultrassônica (PUI)), G2 (NaOCl/HEDP + PUI), G3 (NaOCl + Easy Clean (EC)) and G4 (NaOCl/HEDP + EC). Ao final da ativação, a temperatura (t) foi aferida e comparado com t. inicial. A limpeza de túbulos dentinários foi analisada através de Microscópio Eletrônico de Varredura. PUI aqueceu suavemente as diferentes soluções, Easy Clean teve efeito oposto. A associação de NaOCl com soluções quelantes promoveu limpeza de túbulos

Brazilian Flora 2020: Leveraging the power of a collaborative scientific network

International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora

Núcleos de Ensino da Unesp: artigos 2008

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq