Eugenol mitigated acute lung but not spermatic toxicity of C60 fullerene emulsion in mice

C60 fullerene (C60) is a nano-pollutant that can damage the respiratory system. Eugenol exhibits significant anti-inflammatory and antioxidant properties. We aimed to investigate the time course of C60 emulsion-induced pulmonary and spermatic harms, as well as the effect of eugenol on C60 emulsion toxicity. The first group of mice (protocol 1) received intratracheally C60 emulsion (1.0 mg/kg BW) or vehicle and were tested at 12, 24, 72 and 96 h (F groups) thereafter. The second group of mice (protocol 2) received intratracheally C60 emulsion or vehicle, 1 h later were gavaged with eugenol (150 mg/kg) or vehicle, and experiments were done 24 h after instillation. Lung mechanics, morphology, redox markers, cytokines and epididymal spermatozoa were analyzed. Protocol 1: Tissue damping (G) and elastance (H) were significantly higher in F24 than in others groups, except for H in F72. Morphological and inflammatory parameters were worst at 24 h and subsequently declined until 96 h, whereas redox and spermatic parameters worsened over the whole period. Eugenol eliminated the increase in G, H, cellularity, and cytokines, attenuated oxidative stress induced by C60 exposure, but had no effect on sperm. Hence, exposure to C60 emulsion deteriorated lung morphofunctional, redox and inflammatory characteristics and increased the risk of infertility. Furthermore, eugenol avoided those changes, but did not prevent sperm damage

Acute exposure to C60 fullerene damages pulmonary mitochondrial function and mechanics

C60 fullerene (C60) nanoparticles, a nanomaterial widely used in technology, can offer risks to humans, overcome biological barriers, and deposit onto the lungs. However, data on its putative pulmonary burden are scanty. Recently, the C60 interaction with mitochondria has been described in vitro and in vivo. We hypothesized that C60 impairs lung mechanics and mitochondrial function. Thirty-five male BALB/c mice were randomly divided into two groups intratracheally instilled with vehicle (0.9% NaCl + 1% Tween 80, CTRL) or C60 (1.0 mg/kg, FUL). Twenty-four hours after exposure, 15 FUL and 8 CTRL mice were anesthetized, paralyzed, and mechanically ventilated for the determination of lung mechanics. After euthanasia, the lungs were removed en bloc at end-expiration for histological processing. Lung tissue elastance and viscance were augmented in FUL group. Increased inflammatory cell number, alveolar collapse, septal thickening, and pulmonary edema were detected. In other six FUL and six CTRL mice, mitochondria expressed reduction in state 1 respiration [FUL = 3.0 ± 1.14 vs. CTRL = 4.46 ± 0.9 (SEM) nmol O2/min/mg protein, p = 0.0210], ATP production (FUL = 122.6 ± 18 vs. CTRL = 154.5 ± 14 µmol/100 µg protein, p = 0.0340), and higher oxygen consumption in state 4 [FUL = 12.56 ± 0.9 vs. CTRL = 8.26 ± 0.6], generation of reactive oxygen species (FUL 733.1 ± 169.32 vs. CTRL = 486.39 ± 73.1 nmol/100 µg protein, p = 0.0313) and reason ROS/ATP [FUL = 8.73 ± 2.3 vs. CTRL = 2.99 ± 0.3]. In conclusion, exposure to fullerene C60 impaired pulmonary mechanics and mitochondrial function, increased ROS concentration, and decrease ATP production

O ESTUDO DE DINÂMICA DOS FLUIDOS COM O APLICATIVO WIND TUNNEL: ANALISANDO O VOO DE UM AVIÃO

How can airplanes fly? This work aims to give to students the theoretical basis and practice orientations, in order to given them the conditions of learning to answer this question. We use the Wind Tunnel Applications to study the fluid dynamics by the analysis of a flight of an airplane. In order to achieve our objectives, we propose four activities using this application and materials of easy acquisition. The first one consists in using the aerodynamics profiles of the app, giving to the students the opportunity to explore the subjects exposed by the teacher in the classroom. In the second activity, the students, using the app, will simulate an aerodynamics profile which results the best relation between the lift and the drag. Following the second activity, the students will build their own 3D airplane wing prototypes< using, preferably, low cost materials, like paper, glue, wires, using as a model, the profile chosen and created in the previous activity. Finally, in the fourth activity, the students, will present their projects in the classroom, explaining each step they have followed to achieve their results. As a further step in the study of fluid dynamics, the teacher will promote discussions in the classroom providing recentresearch on the use of superfluids in wind tunnels.Como os aviões conseguem voar? Este trabalho tem como objetivo geral fornecer aos estudantes, fundamentação teórica e orientação prática, a fim de lhes dar as condições de aprendizagem para responder esta pergunta, através de simulações do aplicativo Wind Tunnel no estudo de dinâmica dos fluidos para analisar o voo de um avião. Para alcançar este objetivo são propostas quatro atividades usando os aplicativos e materiais de fácil aquisição. A primeira consiste em utilizar os perfis aerodinâmicos, já existentes no aplicativo, dando aos estudantes a oportunidade de explorar os conteúdos expostos pelo professor em sala de aula. Na segunda atividade, os estudantes, usando o aplicativo, simulariam um perfil aerodinâmico que resulte a melhor relação entre a sustentação e o arrasto. Seguindo a segunda atividade, eles construirão em 3D, o protótipo da asa de avião usando, preferencialmente, materiais de baixo custo, como papel, cola, arame, usando como modelo, o perfil escolhido e criado na atividade anterior. Finalmente, na quarta atividade, os estudantes apresentarão seus projetos na sala de aula, explicando cada passo seguido para alcançar seus resultados. Como um passo além no estudo de dinâmica dos fluidos, o professor promoverá discussões em sala de aula, fornecendo pesquisas recentes sobre o uso de superfluidos em túneis de vento.&nbsp

O ESTUDO DO LOOPING VERTICAL DE UM BALDE COM ÁGUA COM APLICATIVO DE VIDEOANÁLISE PARA DISPOSITIVOS MÓVEIS

The present work presents a proposal of how to explore the vertical looping of a bucket with water using NewtonDV videoanalysis application for mobile devices. With the videoanalysis of the movement, it was possible to verify the force exerted by the bucket on the water at the top of the circular trajectory, also the smaller value of the tangential velocity that keeps the water in the bucket and the force exerted by the bucket on the water at the lowest point of their trajectory. The use of this videoanalysis application allowed to establish an interaction between theory and the application of physical knowledge to concrete situations, enabling learning with different representations such as graphs, diagrams, tables, images and the video itself. In this way, this work is expected to guide the pedagogical action of the teacher, making the smartphones/tablets be seen as a didactic resource for the physics classes.O presente trabalho apresenta uma proposta de como explorar o looping vertical de um balde com água utilizando o aplicativo de videoanálise NewtonDV. Com a análise do vídeo do movimento foi possível verificar a força exercida pelo balde sobre a água no topo da trajetória circular, o menor valor da velocidade tangencial que mantém a água no balde e a força exercida pelo balde sobre a água no ponto mais baixo de sua trajetória. A utilização deste aplicativo de videoanálise permite estabelecer uma interação entre a teoria e a aplicação do conhecimento físico a situações concretas, possibilitando o aprendizado com diferentes representações como gráficos, diagramas, tabelas, imagens e o próprio vídeo. Desta maneira, espera-se que este trabalho norteie a ação pedagógica do professor, fazendo com que os smartphones/tablets sejam vistos como recursos didáticos para as aulas de Física

Clarithromycin-resistant H. pylori primary strains and virulence genotypes in the Northeastern region of Brazil

The increase of H. pylori resistance to clarithromycin is a concern. This study evaluated the prevalence of H. pylori’s primary resistance to clarithromycin and its association with virulence factors in adult dyspeptic patients and asymptomatic children. The gastric mucosa from patients (153 gastritis, 24 gastric cancer, 21 peptic ulcer) and gastric juice obtained by string test from 24 H. pylori and 23S rRNA positive asymptomatic children were included. The clarithromycin resistance was assessed by TaqMan RT-PCR 23S rRNA point mutations, A2142G and/or A2143G, and H. pylori virulence markers by PCR. Overall, the clarithromycin resistance was 14.4% (32/222), 14.2% in adults, and 12% in children, whereas origin, gender, and disease were not distinctive factors. The most prevalent point mutation was A2143G (62.5%). The point mutation was significantly less frequent in cagA-positive (11.4%) than in cagA-negative (23.6%) strains (p=0.03 OR = 0.4 95%CI = 0.19 - 0.91) as well as in cagE-positive (10.2%), cagE-negative (21.2%) (p=0.03 OR: 0.4 I.C:0.20-0.91). No difference was found in iceA or vacA alleles genotypes. Primary resistance to clarithromycin was lower than that reported in Southeast Brazil. The cagA and cagE positive H. pylori samples have few point mutations suggesting that individuals infected with virulent strains may be more susceptible to anti-H. pylori treatment

A VIDEOANÁLISE DE UMA BOLA SALTITANTE: UM ESTUDO SOBRE AS PERDAS DE ENERGIA UTILIZANDO APLICATIVOS PARA SMARTPHONES

Bolas de bilhar que se chocam, nêutrons atirados contra núcleos atômicos em um reator nuclear, o impacto de um meteoro na superfície terrestre, todos esses eventos são exemplos de colisões, um assunto nem sempre bem compreendido pelos estudantes das escolas secundárias. Este trabalho apresenta uma atividade experimental para alunos do ensino secundário com o objetivo de consolidar o estudo de colisões e nortear a ação pedagógica dos professores. Atualmente, a maioria dos estudantes possui um smartphone, cuja utilização na sala de aula para fins de comunicação e redes sociais, tem sido compreensivelmente restringida nas escolas brasileiras. Entretanto podemos utilizar este instrumento como um recurso didático com várias vantagens, principalmente em escolas que sofrem com a falta de laboratórios de ciências. Esses aparelhos possuem diversos sensores e aplicativos que podem facilitar a aprendizagem e o ensino de Física, embora não tenham sido fabricados com este propósito. A possibilidade de realizar experimentos utilizando smartphones, faz com que os alunos adquiram uma maior capacidade de lidar com múltiplas representações, permitindo-lhes desempenhar um papel mais ativo nos processos de resolução de problemas. Foram utilizados dois aplicativos de videoanálises para estudar as perdas de energia em uma colisão entre uma bola de tênis e uma mesa. Obtivemos e analisamos as velocidades em cada eixo, as alturas máximas alcançadas pela bola, a perda de energia cinética após cada impacto com a mesa e o coeficiente de restituição da colisão. A utilização dos recursos do smartphone permitiu estabelecer uma interação entre a teoria e a aplicação do conhecimento físico a situações concretas, possibilitando o aprendizado com diferentes representações como gráficos, diagramas, tabelas, imagens e o próprio vídeo. Isso permitiu aos alunos desempenhar um papel mais ativo a partir da utilização do smartphone como instrumento de medição e análise. Podemos concluir que inserir recursos tecnológicos nas aulas é um caminho simples e possível a todo professor. Esperamos que este trabalho norteie a ação pedagógica dos professores, reduzindo o fosso entre a Ciência e a experiência cotidiana através das tecnologias presentes no dia-a-dia dos alunos

LaMMos - Latching Mechanism based on Motorized-screw for Reconfigurable Robots and Exoskeleton Suits

Reconfigurable robots refer to a category of robots that their components (individual joints and links) can be assembled in multiple configurations and geometries. Most of existing latching mechanisms are based on physical tools such as hooks, cages or magnets, which limit the payload capacity. Therefore, robots re- quire a latching mechanism which can help to reconfigure itself without sacrificing the payload capability. This paper presents a latching mechanism based on the flexible screw attaching principle. In which, actuators are used to move the robot links and joints while connecting them with a motorized-screw and dis- connecting them by unfastening the screw. The brackets used in our mechanism configuration helps to hold maximum force up to 5000N. The LaMMos - Latching Mechanism based on Motorized- screw has been applied to the DeWaLoP - Developing Water Loss Prevention in-pipe robot. It helps the robot to shrink its body to crawl into the pipe with minimum diameter, by recon- figuring the leg positions. And it helps to recover the legs positions to original status once the robot is inside the pipe. Also, LaMMos add stiffness to the robot legs by dynamically integrate them to the structure. Additionally, we present an application of the LaMMos mechanism to exoskeleton suits, for easing the mo- tors from the joints when carrying heavy weights for long periods of time. This mechanism offers many interesting opportunities for robotics research in terms of functionality, pay- load and size.Comment: 14 pages, 15 figure

A IMPORTÂNCIA DA PROTEÇÃO DO COMPLEXO DENTINO-PULPAR E SUAS RESPOSTAS FISIOLÓGICAS A AGENTES AGRESSORES: UMA REVISÃO DE LITERATURA

A dentina e a polpa são tecidos que apresentam inter-relação estrutural e funcional durante toda a vida do órgão dental, essa relação tem início na odontogênese onde a papila dental é responsável pela formação da dentina e da polpa dental

Assessment of the accuracy of portable monitors for halitosis evaluation in subjects without malodor complaint : are they reliable for clinical practice?

Halitosis is defined as a foul odor emanated from the oral cavity, with great impact in quality of life and social restraints. Recently, the use of Breath Alert™ in research increased significantly. Halimeter™, another portable device, is often used in clinical practice. Nevertheless, not many studies have verified the accuracy and compared the results of both devices simultaneously. Objective: To verify the accuracy of Breath Alert™ and Halimeter™ in patients without chief complaint of halitosis, using the organoleptic test (OT) as "gold standard." The second aim was to verify whether their concomitant use could enhance the diagnostic accuracy of halitosis. Material and Methods: A cross-sectional analytical study was performed. The quality of expired air of 34 subjects without chief complaint of halitosis was assessed. Two experienced examiners carried out the OT. Afterward, a third blinded examiner performed Halimeter™ (HT) and Breath Alert™ (BA) tests. Results: The OT identified halitosis in 21 subjects (62%). The area under the ROC curve (95% confidence interval) was 0.67 (0.48-0.85) and 0.54 (0.34-0.75) for HT and BA, respectively. The accuracy for HT and BA was 59% and 47%, respectively. The combined usage of HT and BA provided 11 positive results, being 9 subjects (43%) out of the total of 21 positive cases. Conclusions: Halimeter™ and Breath Alert™ were not able to diagnose halitosis in non-complainer subjects at the same level as the organoleptic examination, since their accuracy were low. Our results suggest that such portable devices are not reliable tools to assess halitosis and may neglect or misdiagnose a considerable number of patients in clinical practice

Production of plywood using veneers of Sequoia sempervirens and urea-formaldehyde resin

ResumoEsta pesquisa teve por objetivo avaliar a qualidade dos painéis compensados multilaminados produzidos com lâminas de madeira de Sequoia sempervirens (D. Don) Endl. Foram produzidos em laboratório compensados com cinco lâminas de 2,0 mm de espessura, colados com resina ureia-formaldeído (UF), com duas diferentes formulações de batida de cola e gramaturas. Os painéis foram prensados com pressão específica de 10 kgf/cm², temperatura de 110 ºC e tempo de prensagem de 10 minutos. Foram avaliadas as propriedades de resistência da linha de cola aos esforços de cisalhamento (RLC) e flexão estática paralelo e perpendicular (MOE e MOR). De uma forma geral, as diferentes formulações da batida de cola e gramaturas não afetaram significativamente os resultados das propriedades dos painéis, o que representa um aspecto importante sob o ponto de vista econômico. Os valores médios de RLC e percentagem de falhas na madeira atendem aos requisitos mínimos da norma EN 314-2 (1993). Os resultados obtidos nesta pesquisa indicam a possibilidade de uso de lâminas de sequoia para o miolo de painéis compensados para uso interior e de forma associada com lâminas de espécies com maior resistência mecânica nas capas.AbstractProduction of plywood using veneers of Sequoia sempervirens and urea-formaldehyde resin. This research was carried out to evaluate the quality of plywood made from wood veneer of Sequoia sempervirens. It was produced in laboratory plywood composed by five veneers with 2.0 mm thick, bonded with urea-formaldehyde resin (UF) with two different formulations of glue and amount of glue spread. The panels were pressed with specific pressure of 10 kgf/cm², temperature of 110 °C and pressing time of 10 minutes. It was evaluated the properties of the glue line shear strength (RLC) and static bending (MOE and MOR) parallel and perpendicular. In general, the different adhesive formulations and amount of spread glue did not significantly affect the results of the properties of the panels, which represent an important aspect on the economic point of view. The mean values of RLC and percentage of wood failure meet minimum requirements of standard EN 314-2 (1993). The results of this research revealed the possibility to using the veneers of sequóia for the core of internal use plywood associated with greater strength species on the faces.Keywords: Wood veneer; sequoia; plywood; urea-formaldehyde.This research was carried out to evaluate the quality of plywood made from wood veneer of Sequoia sempervirens. It was produced in laboratory plywood composed by five veneers with 2.0 mm thick, bonded with urea-formaldehyde resin (UF) with two different formulations of glue and amount of glue spread. The panels were pressed with specific pressure of 10 kgf/cm², temperature of 110 °C and pressing time of 10 minutes. It was evaluated the properties of the glue line shear strength (RLC) and static bending (MOE and MOR) parallel and perpendicular. In general, the different adhesive formulations and amount of spread glue did not significantly affect the results of the properties of the panels, which represent an important aspect on the economic point of view. The mean values of RLC and percentage of wood failure meet minimum requirements of standard EN 314-2 (1993). The results of this research revealed the possibility to using the veneers of sequóia for the core of internal use plywood associated with greater strength species on the faces