14 research outputs found
Effects of Glide Path on the Centering Ability and Preparation Time of Two Reciprocating Instruments
Introduction: The aim of this in vitro study was to evaluate the effects of establishing glide path on the centering ability and preparation time of two single-file reciprocating systems in mesial root canals of mandibular molars. Methods and Materials: Sixty extracted mandibular molars with curvatures of 25-39 degrees and separate foramina for the mesiobuccal and mesiolingual canals, were divided into four groups (n=15); WaveOne+glide path; WaveOne; Reciproc+glide path and Reciproc. Non-patent canals were excluded and only one canal in each tooth was instrumented. A manual glide path was established in first and third groups with #10, 15 and 20 hand K-files. Preparation was performed with reciprocating in-and-out motion, with a 3-4 mm amplitude and slight apical pressure. Initial and final radiographs were taken to analyze the amount of dentin removed in the instrumented canals. The radiographs were superimposed with an image editing software and examined to assess discrepancies at 3-, 6- and 9-mm distances from the apex. The Kruskal-Wallis test was used for statistical analysis. The level of significance was set at 0.05. Results: Preparation in groups without glide paths was swifter than the other groups (P=0.001). However, no difference was observed regarding centering ability. Conclusion: Establishing a glide path increased the total instrumentation time for preparing curved canals with WaveOne and Reciproc instruments. Glide path had no influence on the centering ability of these systems.Keywords: Centering Ability; Glide Path; Reciproc; Root Canal Preparation; Single-File Instrumentation; WaveOn
ÓLEOS ESSENCIAIS DE Blepharocalyx, Nectandra e Piper: ATIVIDADE SOBRE FUNGOS APODRECEDORES DE MADEIRA
This study aimed to use digital image processing to evaluate the antifungal activity of essential oils (EOs) from Blepharocalyx salicifolius (Myrtaceae), Nectandra grandiflora (Lauraceae), Nectandra megapotamica (Lauraceae) and Piper gaudichaudianum (Piperaceae) on wood decay fungi. A white-rot fungus, Trametes versicolor, and a brown-rot fungus, Gloeophyllum trabeum, were selected. The EOs were extracted by hydrodistillation and chemically characterized by gas chromatography coupled to mass spectrometry (GC-MS). The antifungal activity of the EOs was evaluated by the Petri plate diffusion test. The inhibition verification was calculated with the aid of digital image processing, using ImageJ software. The predominant compounds of the B. salicifolius and P. gaudichaudianum extractives were eucalyptol and dillapiol, respectively. For the species of Nectandra, bicyclogermacrene was the most representative constituent of the N. megapotamica EO, whereas dehydrofuquinone was the major constituent of the EOs from N. grandiflora leaves and fruits. The highest growth inhibition of T. versicolor was caused by N. megapotamica EO. The highest inhibition percentages of G. trabeum were provided by P. gaudichaudianum and B. salicifolius extractives. Digital image processing was an effective tool for the accurate analysis of fungal growth.A busca por produtos naturais que possam substituir preservantes da madeira sintéticos é crescente. Dentre estes produtos, estão os óleos essenciais (OEs). Portanto, o objetivo deste estudo foi avaliar a atividade antifúngica dos OEs de Blepharocalyx salicifolius, Nectandra grandiflora, Nectandra megapotamica e Piper gaudichaudianum, sobre os fungos apodrecedores de madeira Trametes versicolor e Gloeophyllum trabeum. Os OEs foram extraídos por hidrodestilação e foram caracterizados quimicamente. A atividade antifúngica dos OEs foi avaliada pelo teste de difusão em placas de Petri. A verificação da inibição foi calculada com auxílio do software ImageJ®. Os componentes majoritários dos OEs de B. salicifolius e P. gaudichaudianum foram eucaliptol e dilapiol, respectivamente. Biciclogermacreno foi o constituinte majoritário do óleo essencial (OE) de folhas de N. megapotamica, enquanto que a deidrofuquinona foi majoritária nos OEs de folhas e frutos de N. grandiflora. A maior inibição do crescimento de T. versicolor foi causada pelo OE de N. megapotamica, com 31,4%. Os maiores percentuais de inibição observados sobre o crescimento de G. trabeum foram proporcionados pelos extrativos de P. gaudichaudianum e B. salicifolius, com 13,9 e 7,5%, respectivamente. Contudo, o resultado deste último não diferiu dos demais OEs avaliados. Os resultados indicaram que o extrativo de espécie de Nectandra que apresentou maior efeito sobre T. versicolor foi N. megapotamica. Entretanto, este gênero não foi tão eficiente contra G. trabeum.
Palavras-chave: biciclogermacreno; deidrofuquinona; dilapiol; eucaliptol; Gloeophyllum trabeum; Trametes versicolor.
Blepharocalyx, Nectandra and Piper essential oils: activity on wood-decay fungi
ABSTRACT: The search for natural products that can replace synthetic wood preservatives is growing. Among these products are essential oils (EOs). Therefore, the aim of this study was to evaluate the antifungal activity of EOs from Blepharocalyx salicifolius , Nectandra grandiflora , Nectandra megapotamica and Piper gaudichaudianum on the wood-rotting fungi Trametes versicolor and Gloeophyllum trabeum. The EOs were extracted by hydrodistillation and chemically characterized. The antifungal activity of the EOs was evaluated by the Petri dish diffusion test. The inhibition verification was calculated using ImageJ® software. The major components of the EOs of B. salicifolius and P. gaudichaudianum were eucalyptol and dillapiol, respectively. Bicyclogermacrene was the major constituent of N. megapotamica leaves essential oil (EO), while dehydrofuquinone was the major constituent of the EOs from N. grandiflora leaves and fruits. The highest growth inhibition of T. versicolor was caused by N. megapotamica EO, with 31.4%. The highest inhibition percentages of G. trabeum growth were provided by P. gaudichaudianum and B. salicifolius extractives, with 13.9 and 7.5%, respectively. However, the result of the latter did not differ from the other EOs evaluated. The results indicated that, from the extractives of Nectandra species, the greatest effect on T. versicolor was detected to N. megapotamica EO. However, this genus was not so efficient against G. trabeum.
Keywords: bicyclogermacrene; dehydrofuquinone; dillapiole; eucalyptol; Gloeophyllum trabeum; Trametes versicolor
12,500+ and counting: biodiversity of the Brazilian Pampa
Knowledge on biodiversity is fundamental for conservation strategies. The Brazilian Pampa region, located in subtropical southern Brazil, is neglected in terms of conservation, and knowledge of its biodiversity is fragmented. We aim to answer the question: how many, and which, species occur in the Brazilian Pampa? In a collaborative effort, we built species lists for plants, animals, bacteria, and fungi that occur in the Brazilian Pampa. We included information on distribution patterns, main habitat types, and conservation status. Our study resulted in referenced lists totaling 12,503 species (12,854 taxa, when considering infraspecific taxonomic categories [or units]). Vascular plants amount to 3,642 species (including 165 Pteridophytes), while algae have 2,046 species (2,378 taxa) and bryophytes 316 species (318 taxa). Fungi (incl. lichenized fungi) contains 1,141 species (1,144 taxa). Animals total 5,358 species (5,372 taxa). Among the latter, vertebrates comprise 1,136 species, while invertebrates are represented by 4,222 species. Our data indicate that, according to current knowledge, the Pampa holds approximately 9% of the Brazilian biodiversity in an area of little more than 2% of Brazil’s total land The proportion of species restricted to the Brazilian Pampa is low (with few groups as exceptions), as it is part of a larger grassland ecoregion and in a transitional climatic setting. Our study yielded considerably higher species numbers than previously known for many species groups; for some, it provides the first published compilation. Further efforts are needed to increase knowledge in the Pampa and other regions of Brazil. Considering the strategic importance of biodiversity and its conservation, appropriate government policies are needed to fund studies on biodiversity, create accessible and constantly updated biodiversity databases, and consider biodiversity in school curricula and other outreach activitie
Long-Lasting Efficacy of Radio Electric Asymmetric Conveyer Neuromodulation Treatment on Functional Dysmetria, an Adaptive Motor Behavior
BackgroundFluctuating asymmetry (FA) is widely defined as the deviation from perfect bilateral symmetry and is considered an epigenetic measure of environmental stress. Rinaldi and Fontani hypothesized that the FA morpho-functional changes originate from an adaptive motor behavior determined by functional alterations in the cerebellum and neural circuits, not caused by a lesion, but induced by environmental stress. They called this phenomenon functional dysmetria (FD). On this premise, they developed the radio electric asymmetric conveyer (REAC) technology, a neuromodulation technology aimed at optimizing the best neuro-psycho-motor strategies in relation to environmental interaction.AimsPrevious studies showed that specific REAC neuro postural optimization (NPO) treatment can induce stable FD recovery. This study aimed to verify the duration of the NPO effect in inducing the stable FD recovery over timeMaterials and methodsData were retrospectively collected from a population of 29,794 subjects who underwent a specific semiological FD assessment and received the NPO treatment, regardless of the pathology referred.ResultsThe analysis of the data collected by the various participants in the study led us to ascertain the disappearance of FD in 100% of the cases treated, with a stability of the result detected up to 18 years after the single administration of the REAC NPO treatment.ConclusionsThe REAC NPO neurobiological modulation treatment consisting of a single administration surprisingly maintains a very long efficacy in the correction of FD. This effect can be explained as the long-lasting capacity of the NPO treatment to induce greater functional efficiency of the brain dynamics as proven in previous studies
Influence of the Caatinga woods secondary metabolites on the resistance of wood decaying fungi
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Florestal, Programa de Pós-Graduação em Ciências Florestais, 2018.Este trabalho avaliou a influência dos metabólitos secundários das espécies de madeiras da Caatinga Pterodon abruptus, Diptychandra aurantiaca, Terminalia fagifolia, Machaerium acutifolium e Aspidosperma multiflorum, na resistência ao ataque de quatro fungos apodrecedores: Trametes versicolor, Pycnoporus sanguineus, Gloeophyllum trabeum e Gloeophyllum striatum. As espécies de madeira foram submetidas ao ensaio de apodrecimento acelerado em laboratório de acordo com ASTM D 2017/05. Em relação ao ataque dos quatro fungos, as espécies Pterodon abruptus e Diptychandra aurantiaca foram classificadas como altamente resistentes e a espécie Machaerium acutifolium foi classificada como resistente. Terminalia fagifolia foi classificada como altamente resistente aos fungos P. sanguineus, G. trabeum e G. striatum, e resistente ao T. versicolor. Aspidosperma multiflorum foi resistente aos fungos de podridão branca e moderadamente resistente aos fungos de podridão parda. De cada espécie madeireira foram obtidos metabólitos secundários pela maceração com metanol, seguida da separação em quatro extratos em razão da polaridade dos solventes utilizados: nhexano, diclorometano, acetato de etila e 1-butanol. Esses extratos foram utilizados para avaliar seu potencial antifúngico em testes de inibição por difusão em placas de Petri. Este teste apresentou resultados semelhantes ao alcançados nos testes de apodrecimento acelerado para todas as espécies, com exceção da T. fagifolia. Quanto aos metabólitos secundários, os compostos presentes no extrato metanólico bruto e extrato hexânico apresentaram maior atividade antifúngica. O estudo se mostrou útil para avaliação de metabólitos secundários com potencial antifúngico em cada um dos extratos de diferentes polaridades.This work evaluated the influence of secondary metabolites of the Caatinga wood species Pterodon abruptus, Diptychandra aurantiaca, Terminalia fagifolia, Machaerium acutifolium and Aspidosperma multiflorum, on the resistance against four wood decaying fungi Trametes versicolor, Pycnoporus sanguineus, Gloeophyllum trabeum and Gloeophyllum striatum. The wood species were submitted to the laboratory accelerated rotting test in accordance with ASTM D 2017/05. In relation to the attack of the four wood decaying fungi, the species Pterodon abruptus and Diptychandra aurantiaca were classified as highly resistant and the specie Machaerium acutifolium was classified as resistant. Terminalia fagifolia was classified as highly resistant to fungi P. sanguineus, G. trabeum and G. striatum, and resistant to T. versicolor. Aspidosperma multiflorum was resistant to white rot fungi and moderately resistant to brown rot fungi. From each species, secondary metabolites were obtained by maceration in methanol, followed by separation in four extracts due to the polarity of the solvents used: nhexane, dichloromethane, ethyl acetate and 1-butanol. These extracts were used to evaluate their antifungal potential on Petri dishes diffusion inhibition tests. This test presented similar results to those obtained in laboratory accelerated rotting test for all species, except for T. fagifolia. For the secondary metabolites, the compounds present in the crude methanolic extract and hexane extract presented higher antifungal activity. The test proved to be useful for the evaluation of secondary metabolites in each one of separated extracts with antifungal potential
In vivo assessment of accuracy of Propex II, Root ZX II, and radiographic measurements for location of the major foramen
Objectives
The aim of this in vivo study was to assess the accuracy of 2 third-generation electronic apex locators (EALs), Propex II (Dentsply Maillefer) and Root ZX II (J. Morita), and radiographic technique for locating the major foramen (MF).
Materials and Methods
Thirty-two premolars with single canals that required extraction were included. Following anesthesia, access, and initial canal preparation with size 10 and 15 K-flex files and SX and S1 rotary ProTaper files, the canals were irrigated with 2.5% sodium hypochlorite. The length of the root canal was verified 3 times for each tooth using the 2 apex locators and once using the radiographic technique. Teeth were extracted and the actual WL was determined using size 15 K-files under a × 25 magnification. The Biostat 4.0 program (AnalystSoft Inc.) was used for comparing the direct measurements with those obtained using radiographic technique and the apex locators. Pearson's correlation analysis and analysis of variance (ANOVA) were used for statistical analyses.
Results
The measurements obtained using the visual method exhibited the strongest correlation with Root ZX II (r = 0.94), followed by Propex II (r = 0.90) and Ingle's technique (r = 0.81; p < 0.001). Descriptive statistics using ANOVA (Tukey's post hoc test) revealed significant differences between the radiographic measurements and both EALs measurements (p < 0.05).
Conclusions
Both EALs presented similar accuracy that was higher than that of the radiographic measurements obtained with Ingle's technique. Our results suggest that the use of these EALs for MF location is more accurate than the use of radiographic measurements
Natural gas hydrates in the Rio Grande Cone (Brazil): A new province in the western South Atlantic
Ex-vivo Smear Layer Removal Efficacy of Two Activated Irrigation Techniques After Reciprocating Instrumentation in Curved Canals
Dismantling Brazil's science threatens global biodiversity heritage
In the middle of a political and fiscal crisis, the Brazilian government is applying successive budget cuts, including in science funding. Recent cuts radically affect research programs on biodiversity that are crucial components for the design and monitoring of public policies for nature conservation and sustainable development. We analyze the consequences of such cuts on the Research Program on Biodiversity (PPBio), the largest biodiversity research network in Brazil (626 researchers, nine networks in all Brazilian biomes). Brazil holds a substantial part of the world's biodiversity and of tropical forests that play a significant role for regional and global climate stability. If underfunding is maintained, the dismantling of the Brazilian PPBio will have consequences that go beyond biodiversity knowledge itself but affect society as a whole. Brazil will likely fail to reach the National Targets for Biodiversity 2011–2020, and it will be difficult to fulfill the restoration target of the Brazilian NDC and to advance with the sustainable development goals. © 2017 Associação Brasileira de Ciência Ecológica e Conservaçã
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12,500+ and counting: biodiversity of the Brazilian Pampa
Knowledge on biodiversity is fundamental for conservation strategies. The Brazilian Pampa region, located in subtropical southern Brazil, is neglected in terms of conservation, and knowledge of its biodiversity is fragmented. We aim to answer the question: how many, and which, species occur in the Brazilian Pampa? In a collaborative effort, we built species lists for plants, animals, bacteria, and fungi that occur in the Brazilian Pampa. We included information on distribution patterns, main habitat types, and conservation status. Our study resulted in referenced lists totaling 12,503 species (12,854 taxa, when considering infraspecific taxonomic categories [or units]). Vascular plants amount to 3,642 species (including 165 Pteridophytes), while algae have 2,046 species (2,378 taxa) and bryophytes 316 species (318 taxa). Fungi (incl. lichenized fungi) contains 1,141 species (1,144 taxa). Animals total 5,358 species (5,372 taxa). Among the latter, vertebrates comprise 1,136 species, while invertebrates are represented by 4,222 species. Our data indicate that, according to current knowledge, the Pampa holds approximately 9% of the Brazilian biodiversity in an area of little more than 2% of Brazil’s total land. The proportion of species restricted to the Brazilian Pampa is low (with few groups as exceptions), as it is part of a larger grassland ecoregion and in a transitional climatic setting. Our study yielded considerably higher species numbers than previously known for many species groups; for some, it provides the first published compilation. Further efforts are needed to increase knowledge in the Pampa and other regions of Brazil. Considering the strategic importance of biodiversity and its conservation, appropriate government policies are needed to fund studies on biodiversity, create accessible and constantly updated biodiversity databases, and consider biodiversity in school curricula and other outreach activities