A dengue evoluiu de uma doença restrita a alguns países para um grave problema global de saúde pública, atingindo mais de 120 países nos últimos anos. No Brasil, após sua reintrodução em 1981, o país enfrentou diversas epidemias, com mais de 16 milhões de casos registrados até o momento. Em 2023, sob a vigência do fenômeno climático El Niño registrou-se uma das maiores epidemias de dengue no país, com mais de 1,6 milhões de casos notificados. Temperaturas e pluviosidade mais elevadas em conjunto com a circulação simultânea dos quatro sorotipos do vírus da dengue aumentaram ainda mais o risco de disseminação da doença em 2024, especialmente em populações sem imunidade para alguns dos sorotipos. Diante deste quadro, o Ministério da Saúde promoveu várias ações para enfrentar a situação, incluindo a instalação de uma Sala Nacional de Arboviroses e um Comitê de Operações de Emergência, repasses financeiros para apoiar estados e municípios em ações contingenciais de vigilância e prevenção de doenças, com ênfase no enfrentamento das arboviroses e investimentos em inovações para o controle da dengue, como vacinação e o método Wolbachia. Ainda assim, o primeiro trimestre de 2024 registrou um número de casos suspeitos de dengue superior ao de 2023, destacando a necessidade de aprimoramentos no monitoramento da situação epidemiológica para detecção precoce de epidemias e da preparação dos serviços de saúde para o cuidado dos casos com sinais de gravidade. Após mais de 40 anos de epidemias recorrentes, o controle efetivo da dengue no país requer ações sustentadas de prevenção por meio de estratégias inovadoras, envolvendo esforços coordenados de todas as esferas da gestão em saúde, juntamente com a participação ativa da população. Ações estruturais para a melhoria na cobertura de saneamento básico e para mitigação dos efeitos das mudanças climá

Dengue has evolved from a disease restricted to a few countries into a serious global public health issue, affecting over 120 countries in recent years. In Brazil, after its reintroduction in 1981, the country has faced several epidemics, with over 16 million cases registered to date. In 2023, under the influence of the El Niño climatic phenomenon, one of the largest epidemics occurred in the country, with over 1.6 million cases reported. High temperatures and precipitation in line with the simultaneous circulation of all four serotypes of the dengue virus increased the risk of disease spread in 2024, especially in populations without immunity to some of the serotypes. In such a scenario, the Ministry of Health undertook various actions to address the situation, including the establishment of a National Arbovirus Situation Room and an Emergency Operations Commitee, financial support to assist states and municipalities in contingency actions for disease surveillance and prevention, with an emphasis on combating arboviruses, and investments in innovations for dengue control, such as vaccination and the Wolbachia method. However, the number of notified dengue cases in the first trimester of 2024 supplanted the whole year of 2023, highlighting the need for a more effective monitoring of the epidemiological situation for early outbreak detection and the preparation of health services for the care of cases with signs of severity. After more than 40 years of recurrent dengue epidemics, the effective control of dengue requires sustained preventive actions using innovative strategies, with coordinated efforts at all levels of health management, along with active participation of the population. Structural actions to improve basic sanitation coverage and to mitigate the effects of climate change are critical conditions for reducing the burden of dengue in the population.

Abstract The shape of the galls can be adjusted by factors such as natural enemies and climatic conditions to which the galls are subjected. Studies that evaluate the climatic regime as a possible driver of the morphology of galls are scarce and do not consider Neotropical systems. To fill this knowledge gap, this study evaluated the influence of seasonality on the morphology of Cecidomyiidae galls induced on Myrcia neoobscura (Myrtaceae) growing in the Cerrado of Bahia. A total of 270 galls were sampled during the dry and rainy seasons. The average monthly precipitation was obtained. The galls were refrigerated, weighed, and measured within 72 h of collection. The average weight of the galls ranged from 0.106 g to 0.780 g; while, the volume ranged from 35.07 mm3 to 726.70 mm3 and the surface area from 20.03 mm2 to 719.57 mm2. The average weight, volume, and surface area of galls were approximately 50% higher during the rainy season than during the dry season. These three variables were also positively related to average precipitation. These results support the hypothesis that seasonality may contribute to the observed variation in the final shape of galls on a local scale.

ABSTRACT The coffee leaf miner is responsible for significant decreases in coffee production. To mitigate the problems caused by this pest control strategies need to be applied. The combined application of chemical and biological insecticides is an alternative that can reduce the population of leaf miner in areas with high infestation and occurrence of resistant individuals. The objective of this study was to evaluate the combined application of Isaria fumosorosea and beta-cyfluthrin in the control of coffee leaf miner. A randomized block design was used, in a 4 x 2 factorial scheme, with four treatments: I. fumosorosea, beta-cyfluthrin, I fumosorosea + beta-cyfluthrin and control, besides two application levels, one and two applications. There was no significant effect on the interaction between treatments. The number of applications did not increase the control percentage of the leaf miner. However, the treatments I. fumosorosea, beta-cyfluthrin, I fumosorosea + beta-cyfluthrin showed a higher control percentage of the leaf miner, compared to the control treatment with both one and two applications. I. fumosorosea, beta-cyfluthrin, and the combination of I fumosorosea + beta-cyfluthrin are effective in controlling the leaf miner.

Resumo: Os sistemas remanescentes de água doce estão historicamente ameaçados, principalmente devido às atividades humanas, como agricultura e urbanização. As consequências de tais atividades são inúmeras, e entre elas há a diminuição de habitats adequados para a fauna ameaçada. No cerrado brasileiro, a odonatofauna de veredas e matas ripárias ainda são pouco exploradas, fato que dificulta os esforços de conservação do grupo. Assim, realizamos um inventário em diversos pontos urbanos e rurais com essas fitofisionomias em Uberlândia, na região do Triângulo Mineiro, oeste de Minas Gerais. No total, foram encontradas 101 espécies de Odonata, sete famílias e 46 gêneros no município, com 76 e 66 espécies, respectivamente, pertencentes a pontos de veredas e de matas. Dessa diversidade, oito espécies foram os primeiros registros no estado de Minas Gerais: Neuraeschna claviforcipata Martin, 1909, Phyllocycla cf. medusa Belle, 1988, Diastatops intensa Montgomery, 1940, Oligoclada pachystigma Karsch, 1890, O. xanthopleura Borror, 1931, Angelagrion nathaliaeLencioni, 2008, Telebasis sanguinalis Calvert, 1909 e Telebasis simulacrum (Calvert, 1909). Nós também coletamos Erythrodiplax anaGuillermo-Ferreira & Vilela 2016, uma espécie listada como em perigo (EN) pela lista vermelha da IUCN. Além disso, incluímos algumas notas taxonômicas de fêmeas de Forcepsioneura machadorum, uma espécie recém-descoberta na região. Nossos resultados contribuem para o banco de dados Odonata no Brasil e destacam a importância dos inventários em ecossistemas aquáticos pouco explorados.

Abstract: Remaining freshwater systems are historically under threat mainly due to human activities such as agriculture and urbanization. The consequences of such activities are innumerous, and among them there is a decrease of suitable habitats for threatened fauna. In the Brazilian Cerrado, the odonatofauna of palm swamps and riparian forests are still poorly explored, a fact that difficult conservation efforts of the group. Thus, we performed an inventory in several urban and rural sites containing these phytophysiognomies in Uberlândia, Triângulo Mineiro region, western Minas Gerais state. In total, we found 101 Odonata species, seven families and 46 genera in the municipality, with 76 and 66 species, respectively, belonging to palm swamp and forest sites. From this diversity, eight species were first records in the state of Minas Gerais: Neuraeschna claviforcipata Martin, 1909, Phyllocycla cf. medusaBelle, 1988, Diastatops intensa Montgomery, 1940, Oligoclada pachystigma Karsch, 1890, O. xanthopleura Borror, 1931, Angelagrion nathaliaeLencioni, 2008, Telebasis sanguinalis Calvert, 1909 and Telebasis simulacrum (Calvert, 1909). We also sampled Erythrodiplax anaGuillermo-Ferreira & Vilela 2016, a species listed as endangered (EN) by the IUCN red list. Additionally, we include some taxonomic notes of Forcepsioneura machadorum females, a newly discovered species in the region. Our results contribute to the Odonata database in Brazil and highlights the importance inventories in poorly explored aquatic ecosystems.

Resumo: A Caatinga é uma floresta tropical sazonalmente seca, uma das mais ricas em espécies vegetais. Infelizmente, muitos grupos de insetos herbívoros associados a essas plantas são pouco conhecidos. Este estudo teve como objetivo investigar a diversidade de insetos galhadores (IG) e plantas hospedeiras (PH) na Caatinga. Para isso, nós compilamos as informações disponíveis na literatura de inventários sobre a comunidade de IG e suas PH, e as espécies descritas de cecidomiídeos. Nós encontramos 100 espécies, 72 gêneros e 32 famílias de PH abrigando um total de 156 morfoespécies de IG e 12 espécies descritas de cecidomiídeos. Espécies de plantas com apenas uma espécie de IG representaram 74% das hospedeiras, mas para as super PH (ou seja, PH com alto número de IG), apesar do pequeno número de espécies de PH, havia muitas espécies de IG. Fabaceae foi a família mais rica, com 30% das espécies de PH e 40% dos IG. Além disso, nossos resultados mostraram um baixo número de espécies de PH e IG para a Caatinga brasileira, e discutimos esse padrão com os seguintes argumentos, primeiro, é provável que o número de inventários de insetos galhadores para a Caatinga seja subamostrado, segundo a Caatinga possui um número relativamente menor de espécies vegetais quando comparada a outros biomas e, por fim, argumentamos que a Caatinga é uma floresta tropical sazonalmente seca onde a deciduidade representa um fator relevante para as taxas de colonização e desempenho dos IG.

Abstract: Caatinga is a seasonally dry tropical forest, one of the richest in plant species. Unfortunately, many groups of herbivorous insects associated with these plants are poorly known. This study aimed to investigate the diversity of gall-inducing insects (GII) and host plants (HP) in the Caatinga. For this, we compiled the information available in the literature of inventories on GII and their HP communities, and the described gall midge species. We found 100 species, 72 genera, and 32 families of HP hosting a total of 156 morphospecies of GII and 12 species of described cecidomyiids. Plant species with only one GII species represented 74% of hosts, but in super HP (i.e., HP with a high number of GII), despite the small number of HP species, there were many GII species. Fabaceae was also the most specious family, with 30% of HP species and 40% of GII. Furthermore, our results showed a low number of species of HP and GII for the Brazilian Caatinga, that we discussed this pattern with the following arguments, first, it is likely that the number of galling insect inventories for the Caatinga is under-sampled, second the Caatinga has a relatively smaller number of plant species when compared to other biomes, and finally, we argue that the Caatinga is a seasonally dry tropical forest where the deciduousness represents a relevant factor in the colonization and performance rates of GII.

RESUMO Objetivo: Avaliar a hidratação de adolescentes obesos e não obesos por meio dos gráficos da análise vetorial por bioimpedância (BIVA), além de verificar as associações entre a obesidade e os parâmetros da BIVA. Métodos: Estudo transversal realizado com adolescentes entre 14 e 18 anos (n=489, 300 meninos e 189 meninas). A bioimpedância elétrica (BIA; Quantum_II, RJL system, Roma, Itália) ofereceu os parâmetros de resistência e reactância para calcular o ângulo de fase (AF), a massa livre de gordura (MLG) e a gordura corporal (GC). As elipses de confiança foram comparadas e a construção das elipses de tolerância permitiu a avaliação individual e a qualitativa dos vetores e, ainda, a classificação em desidratados, normohidratados e hiper-hidratados. Resultados: Participaram do estudo 78 adolescentes obesos e 411 eutróficos. A resistência (p<0,001), a reactância (p<0,001) e a normalização desses pela estatura (p<0,001) estavam reduzidas nos obesos, enquanto o AF foi superior (p=0,003). O percentual de gordura corporal (%GC) foi 11,3% maior nos adolescentes obesos. O vetor principal dos obesos, tanto masculino (Distância de Mahalanobis (D)=1,38; p<0,001) quanto feminino (D=1,49; p<0,001), indicou maior hidratação. A elipse de tolerância da amostra total mostrou que 25 adolescentes (32,1%) estavam hiper-hidratados e dois (2,6%) vetores posicionados no sentido de desidratação. Dezessete (53,2%) meninas e 16 (34,8%) meninos estavam hiper-hidratados. A regressão logística mostrou relação inversa do índice de massa corpórea (IMC) com a resistência (p<0,001) e a reactância (p<0,001), ambas normalizadas pela estatura. Os adolescentes com aumento do AF (p<0,001) apresentaram duas vezes mais chances de serem classificados como obesos. Conclusões: Os adolescentes obesos estavam hiper-hidratados e houve relação inversa do IMC com a resistência e direta com o AF.

ABSTRACT Objective: To evaluate the hydration of obese and non-obese adolescents by vectorial bioimpedance analysis, in addition to verifying the associations between obesity and bioelectrical impedance vectorial analysis (BIVA) parameters. Methods: A cross-sectional study with adolescents between 14 and 18 years old (n=489, 300 boys and 189 girls). Electric bioimpedance (BIA; Quantum_II, RJL system, Rome, Italy) provided resistance and reactance parameters to calculate phase angle (PA), fat-free mass (FFM) and body fat (%BF). The confidence ellipses were compared, and the construction of the tolerance ellipses allowed individual and qualitative evaluation of the vectors and classification in dehydrated, normohydrated and hyperhydrated. Results: 78 obese and 411 eutrophic adolescents participated. Resistance (p<0.001) and reactance (p<0.001) and their normalization by stature (p<0.001) were reduced in the obese, whereas the PA was higher (p=0.003). %BF was 11.3% higher in obese adolescents. The main vector of the obese, both male (D=1.38; p<0.001) and female (D=1.49; p<0.001), indicated greater hydration. The ellipse of tolerance of the total sample showed that 25 (32.1%) were hyperhydrated and 02 (2.6%) vectors positioned in the sense of dehydration. A total of 17 (53.2%) girls and 16 (34.8%) boys were hyperhydrated. Logistic regression showed an inverse relation of BMI with resistance (p<0.001), reactance (p<0.001) and both normalized by stature. Adolescents with increased PA (p<0.001) were twice as likely to present obesity. Conclusions: Obese adolescents were hyperhydrated and there was an inverse relationship of BMI with resistance and direct with PA.

ABSTRACT The scheduling of jobs over a single machine with sequence dependent setups is a classical problem setting that appears in many practical applications in production planning and logistics. In this work, we analyze six mixed-integer formulation paradigms for this classical context considering release dates and two objective functions: the total weighted completion time and the total weighted tardiness. For each paradigm, we present and discuss a MIP formulation, introducing in some cases new constraints to improve performance. A dominance hierarchy in terms of strength of their linear relaxations bounds is developed. We report extensive computational experiments on a variety of instances to capture several aspects of practical situations, allowing a comparison regarding size, linear relaxation and overall performance. Based on the results, discussions and recommendations are made for the considered problems.

RESUMO Os objetivos deste estudo foram avaliar e correlacionar dados do banco de sementes do solo e do dossel (abertura de dossel-% Canopy Openness e índice de área foliar-IAF) em uma área minerada em processo de restauração por regeneração natural. A área de estudo localiza-se na Zona da Mata Mineira, que apresenta predomínio de Florestas Estacionais Semideciduais, e possui área de 0.50 ha em processo de regeneração natural após 6 anos da exploração de bauxita (sem nenhuma intervenção). Foram plotadas 10 parcelas de 45x29cm ao longo da área, distribuídas de forma a representar toda a porção em processo de restauração. Nestas parcelas foram avaliadas a diversidade do banco de sementes e as características de dossel, estas últimas coletadas através de uma câmera fotográfica NIKON D40X com lente de 8 mm (fisheye). Como resultados foram encontrados 8.280 indivíduos arbóreos, arbustivos, herbáceos e trepadeiras, totalizando 51 espécies e 24 famílias botânicas. O índice de diversidade de Shannon (H’) foi 2,770 e a equabilidade (J) foi 0,705, demonstrando assim uma média diversidade florística desta área, com densidade de 2.114,94 sementes germinadas m-². Através da análise do banco de sementes verificou-se a presença de espécies exóticas na área (23,5%), domínio de espécies pioneiras (68,6%), assim como a predominância de espécies dispersas por anemocoria (52,9%). Quanto às características do dossel, verificou-se uma grande variação existente em diferentes pontos da área, podendo também ser identificado certos padrões de existência de determinadas espécies herbáceas em função da abertura do dossel (menor cobertura vegetal/clareiras), bem como em função da proximidade espacial entre as parcelas plotadas, comprovando assim a alta correlação entre estas duas variáveis e sua importância no processo de restauração florestal.

ABSTRACT The objective of this study was to evaluate and correlate information about soil seed bank and canopy (%Canopy Openness and Leaf area index-LAI) in a mined area in restoration process through natural regeneration. The study area is located in Zona da Mata of Minas Gerais, which presents predominance of Semideciduous Seasonal Forest, and has an area of 0.5 ha in process of natural regeneration after six years of bauxite exploitation (without any intervention). Along the area, ten plots of 45x29cm were allocated and distributed in the best way to represent the whole area in restoration process. Seed bank diversity and canopy characteristics were evaluated in these plots, the last one using a NIKON D40X photographic camera, with fisheye lens of 8mm. As results, 8280 individuals (tree, shrub, herbs, and vines) were found, totaling 51 species and 24 botanical families. The Shannon diversity index (H’) was 2.770, and the equability (J) was 0.705, which demonstrate an average diversity in this area, with a density of 2114.94 germinated seeds m-2. Through the evaluation of the seed bank, the presence of exotic species (23.5%), the dominance of the pioneer species (68.6%), as well as high dispersal by wind (52.9%) were verified in the area. According to canopy characteristics, a significant variation between different points/regions within the study area was found, while patterns of existence of certain herbs as a function of canopy openness (lower vegetal cover/clearings) were also identified, as well as in response to spatial proximity between the allocated plots, confirming the high correlation between these two variables and their importance in the process of forest restoration.

Abstract Dragonflies and damselflies (Insecta: Odonata) are widely distributed among freshwater ecosystems of tropical and temperate environments. They are also particularly sensitive to anthropogenic changes. The objective of this study was to inventory the odonate fauna of a section of the Sucupira Reservoir on Rio Uberabinha, Uberlândia, Minas Gerais, Brazil, and to document the species composition of the odonate fauna during the dry and rainy seasons. The study also aimed to describe the distribution of the sampled species in Brazilian states. Sampling took place in August and September of 2017 (dry season) and in February and March of 2018 (rainy season), and recorded 860 individuals of 43 species belonging to 26 genera and six families. Six new records representing the families Gomphidae, Libellulidae and Coenagrionidae were recorded for the state of Minas Gerais. Seventeen species were collected only during the rainy season and eight only during the dry season, while 18 species were found in both seasons. The rainy season had greater abundance, with four times as many individuals as the dry season. This study increases the number of records for Odonata in the Minas Gerais state, and reinforces the trend for greater predominance of this group during the rainy season in this biome.

RESUMO Objetivo: Avaliar as pressões de ruptura dos adesivos teciduais de Cianoacrilato (Omnex®) e de Fibrina (Evicel®), usados como reforço em suturas colônicas de suínos “ex-vivo”. Métodos: Os procedimentos cirúrgicos realizados foram realizados no Laboratório de Técnica Cirúrgica. A partir da divisão em segmentos de 10 cm do colo descendente e colo sigmoide de três suínas fêmeas ex-vivo, da raça Landrace, ressecados em tempo inferior a seis horas em relação ao momento do abate, foram selecionados 30 segmentos, 10 de cada animal. Foram armazenados em soro fisiológico 0,9% a 36 °C, alocando-se aleatoriamente esses segmentos em três grupos (Controle, Evicel e Omnex) com 10 segmentos cada. Resultados: Os menores e maiores valores pressóricos encontrados nos grupos Controle, Evicel e Omnex foram 36 mmHg e 41 mmHg, 70 mmHg e 90 mmHg, 90 mmHg e 120 mmHg, respectivamente. Com significância estatística (Valor-p < 0,0001) para as comparações 2 a 2 (Sutura, Evicel e Omnex) com um intervalo de confiança de 95% construído a partir da aplicação do método de Turkey. Conclusão: A partir desse estudo conclui-se que o uso de adesivos teciduais em anastomoses colônicas, em modelo experimental animal de suíno ex-vivo, aumentou as pressões de ruptura das anastomoses. Dentre os adesivos testados, o adesivo de Cianoacrilato apresentou maiores pressões de ruptura em relação ao adesivo de Fibrina.

ABSTRACT Aim: To evaluate rupture pressures of tissue adhesives of cyanoacrylate (Omnex®) and fibrin (Evicel®), used as reinforcement in colonic suture from “ex vivo” swine. Methods: Surgical procedures were performed in the Surgical Technique Laboratory. From a division in segments of 10 cm of descending colon and sigmoid colon from three “ex vivo” female swine, Landrace breed, which were resected in less than six hours after the slaughter time, 30 segments were selected, 10 of each animal. They were stored in saline solution 0.9% at 36 °C, being randomly allocated in three groups (Control, Evicel and Omnex), each one containing 10 segments. Results: The lower and higher pressure values found in the groups Control, Evicel and Omnex were 36 mmHg and 41 mmHg, 70 mmHg and 90 mmHg, 90 mmHg and 120 mmHg, respectively. Containing statistical significance (p-value <0.0001) concerning the 2 to 2 comparisons (Control, Evicel and Omnex) with 95% trusting rate based on the application of the Turkey Method. Conclusion: One concludes that the use of tissue adhesives in anastomoses colonic in an experimental animal model of “ex vivo” swine increased the anastomoses rupture pressures. Among the tested adhesives, cyanoacrylate presented higher rupture pressure in relation to fibrin adhesive.

ABSTRACT For pioneer plants, shaded habitats represent a stressful condition, where sunlight exposure is below the optimum level and so leaves expand in order to intercept a greater amount of light. We investigated changes in both phenotypic variation and stress of Bauhinia brevipes in sunny and shaded microhabitats. Leaf area was used as a measure of phenotypic variation, whereas leaf asymmetry (difference between right and left sides of leaves), was used as a measure of stress. We hypothesized an increase in leaf area and stress in shaded locations, which might indicate that B. brevipes was compensating for low light absorption, and elevated levels of stress, respectively. Plants in the sun fitted a fluctuating asymmetry pattern (normal distribution of right minus left sides), while shaded plants were clearly antisymmetric (bimodal distribution of leaf side differences). Leaf asymmetry and area were 5% and 26.8% higher in plants in the shade compared to plants in the sun, respectively. These results were expected since B. brevipes is found predominantly in open areas; so sunlight exposure is important for its development. The presence of antisymmetry is rare in studies of developmental instability, and here it might indicate higher stress compared to plants with fluctuating asymmetry.

Resumo O uso de placebo em pesquisa clínica tem sido motivo de debate nos últimos anos, sobretudo após a Associação Médica Mundial publicar, em 2002, nota de esclarecimento do parágrafo 29 da Declaração de Helsinki. O Brasil tem se destacado por sua posição firme e contrária ao uso flexível de placebo. Tanto o Conselho Federal de Medicina quanto o Conselho Nacional de Saúde editaram resoluções que normatizam seu uso no Brasil, de forma a não admiti-lo em caso da existência de um método terapêutico melhor. O presente artigo reforça essa posição e tem por objetivo descrever as diversas aplicações de placebo em pesquisa clínica, bem como trazer à luz a complexa decisão sobre a eticidade de seu uso. Além disso, os autores propõem uma reflexão acerca da utilização de placebo no âmbito da pesquisa, por meio de algoritmos decisórios baseados nas normativas éticas brasileiras.

Abstract The use of placebos in clinical research has been a matter of considerable debate in recent years, notably when the World Medical Association published, in 2002, a note of clarification for paragraph 29 of the Helsinki Declaration. Brazil is known for its strong opposition to the flexible use of placebos. Both the Federal Council of Medicine and the National Health Council have published resolutions regulating the use of placebos in Brazil, preventing their use if there is a more effective therapeutic method already in place. The present study reinforces that position and aims to describe the various uses of placebos in clinical research, as well as examining the complex decisions relating to the ethics of their use. Additionally, the authors propose a reflection on the use of placebos through decision-making algorithms based on Brazilian ethical standards.

Resumen El uso del placebo en la investigación clínica ha sido un tema de debate en los últimos años, sobre todo después de que la Asociación Médica Mundial publicara, en 2002, una nota aclaratoria del párrafo 29 de la Declaración de Helsinki. Brasil se ha destacado por su firme posición en contra de la utilización flexible del placebo. Tanto el Consejo Federal de Medicina como el Consejo Nacional de Salud editaron resoluciones que regulan el uso del placebo en Brasil, no admitiéndose su uso cuando existe un mejor método terapéutico. El presente artículo refuerza esa posición y tiene como objetivo describir diferentes usos del placebo en la investigación clínica, así como contribuir en la discusión sobre la ética de su uso. Además, los autores proponen una reflexión sobre el uso del placebo en la investigación a través de algoritmos para la toma de decisiones, los cuales se basan en las normativas éticas de Brasil.

This study aimed to guide the planning of anticurvature filing using pre-determined anatomical points on teeth to establish directions for proper implementation of the technique. Two hundred digital periapical radiographs of human molar teeth were selected and divided into two groups (n = 100): MX (maxillary) and MD (mandibular) molars. Mesiobuccal roots were considered for the MX group and mesial roots for the MD group. Pre-determined anatomical points required for planning the anticurvature filing on the root canal path were located, and the distances between these points obtained. The anticurvature filing was simulated in two different protocols for each group, and the region of dentin removal and the remaining dentin thickness were measured in the safety and danger zones of the root canals. Statistical analysis was carried out at a significance level of 5%. The distances between the anatomical points and the thickness of remaining dentin showed significant differences when the two groups were compared (p < 0.001). No significant differences were found between the two experimental groups regarding the area of dentin removal at the root region, but differences were detected in comparison with dentin removal at the crown (p < 0.001). In terms of wear produced after simulation of both anticurvature filing protocols, significant differences were verified for all regions, except for the dentin remaining at the danger zone. The radiographic location of anatomical points allows for planning and implementation of controlled and efficient anticurvature filing and can be performed in the same manner for maxillary and mandibular molars.

Este estudo avaliou a anatomia do canal radicular de incisivos inferiores, antes e após a instrumentação endodôntica, identificando regiões inacessíveis à ação das limas (Área Crítica de instrumentação - AC), em uma perspectiva tridimensional. Trinta incisivos centrais inferiores humanos foram selecionados, divididos em dois grupos (n=15), e instrumentados usando limas rotatórias ProTaper Universal. No grupo RX, imagens longitudinais foram obtidas em duas incidências, vestíbulo-lingual (VL) e mésio-distal (MD), por meio de radiografias digitais. No grupo CT, imagens transversais foram obtidas por meio de microtomografia computadorizada (μTC), em secções localizadas a 3 mm, 9 mm, e 15 mm do ápice. A área do canal das amostras foi avaliada antes e após a instrumentação usando as imagens digitais de cada grupo. Os dados foram analisados por meio do teste t, ANOVA a um critério com parcela subdividida e ao teste de Tukey (α=0,05). A área de canal encontrada nas radiografias MD foi maior do que nas radiografias VL, o que também foi confirmado nas imagens transversais (p<0,01). A Área Crítica de instrumentação só foi detectada nas radiografias MD e nas seções de μTC. Na configuração de canal, a redução contínua na conicidade do canal foi observada nas radiografias VL, enquanto na incidência MD, houve uma constrição no terço cervical e um subsequente aumento no terço médio (p<0,01). A forma cônica do canal radicular foi observada somente na visão VL. O alargamento do canal verificado nas radiografias VL não foi indicativo de instrumentação homogênea, uma vez que áreas não instrumentadas (AC) foram observadas nas paredes vestibular e lingual em visões distintas.

The aim of this study was to evaluate the root canal anatomy of mandibular incisors before and after endodontic instrumentation, identifying regions inaccessible to the action of files (Critical instrumentation Area - CA) in a three-dimensional perspective. Thirty human mandibular central incisors were selected, assigned to two groups (n=15) and instrumented using ProTaper Universal rotary files. In the RX group, longitudinal digital radiographic images were obtained in the buccolingual (BL) and mesiodistal (MD) views. In the CT group, cross-sectional micro-computed tomography (µCT) images were obtained at 3, 9 and 15 mm from the apex. The canal area of the specimens was evaluated before and after instrumentation using digital images from each group. Data were analyzed using t-test, one-way ANOVA with subdivided parcels and Tukey's test (α=0.05). The canal area found in the MD radiographs was larger than in the BL radiographs, which was also confirmed in the transversal images (p<0.01). The CA was only detected in the MD radiographs and µCT scans. On the root canal configuration, a continuous reduction in the canal conicity was observed in BL radiographs, while in MD view there was a constriction at the cervical third and subsequent increase at the middle third (p<0.01). The conical shape of the root canal was observed only in the BL view. The canal enlargement in BL radiographs was not indicative of homogeneous instrumentation, since unprepared areas (CA) were also verified on the buccal and lingual walls in different images

O objetivo deste estudo foi avaliar propriedades físico-químicas e biológicas de novos cimentos experimentais (Híbrido, Pasta e Resinoso) baseado na combinação sinérgica de materiais existentes, incluindo pH, resistência à tração diametral (RTD) e citotoxidade, comparando-os ao MTA (Angelus®) e a um cimento de ionômero de vidro (CIV) desenvolvido em nosso laboratório. Para a realização dos testes físico-mecânico e biológico, foram confeccionados espécimes com dimensões padrão. O teste de pH foi realizado por meio de pH-metro digital nos tempos: 3, 24, 48 e 72 h. Para o teste de RTD, espécimes cilíndricos foram submetidos a carga compressiva até sua fratura. Para avaliação da citotoxidade, utilizou-se o teste MTT. Os dados foram analisados utilizando ANOVA e teste de Tukey (α=0,05). O grupo Pasta apresentou valores de pH semelhantes ao MTA, assim como o grupo Híbrido seguiu os parâmetros do CIV (p>0,05). Todos os materiais apresentaram valores de pH alcalinos ou próximosà neutralidade nos tempos avaliados. MTA e CIV apresentaram valores de RTD similares. Os menores e maiores valores observados foram do grupo Pasta e Resinoso, respectivamente (p<0,05). A viabilidade celular para os grupos MTA, Híbrido, Pasta, Resinoso, quando comparados ao grupo controle foi de: 49, 93, 90 e 86%, respectivamente. O cimento experimental Resinoso apresentou desempenho similar ou superior aos materiais comerciais e experimentais avaliados

This aim of this study was to evaluate the physicochemical and biological properties of novel experimental cements (Hybrid, Paste and Resin) based on synergistic combinations of existing materials, including pH, diametral tensile strength (DTS) and cytotoxicity comparing them with mineral trioxide aggregate (MTA - Angelus®) and a glass ionomer cement (GIC) developed at our laboratory. For the physicochemical and biological tests, specimens with standard dimensions were produced. pH measurements were performed with digital pH meter at the following time intervals: 3, 24, 48 and 72 h. For the DTS test, cylindrical specimens were subjected to compressive load until fracture. The MTT assay was performed for cytotoxicity evaluation. Data were analyzed by ANOVA and Tukey's test (α=0.05). Paste group showed pH values similar to MTA, and Hybrid group presented pH values similar to GIC (p>0.05). The tested materials showed pH values ranging from alkaline to near neutrality at the evaluated times. MTA and GIC showed similar DTS values. The lowest and highest DTS values were seen in the Paste and Resin groups, respectively (p<0.05). Cell viability for MTA and experimental Hybrid, Paste and Resin groups was 49%, 93%, 90% and 86%, respectively, when compared with the control group. The photo-cured experimental resin cement showed similar or superior performance compared with the current commercial or other tested experimental materials.