Ecological anatomy of Eugenia glazioviana Kiaersk leaf (Myrtaceae)

Dos mecanismos com potencial valor adaptativo em resposta ao estresse hídrico merece destaque o apresentado por Eugenia glazioviana Kiaersk cuja perda de turgescência foliar e consequente curvatura do limbo da posição horizontal para a vertical, sem a abscisão das folhas, que estão associados à redução da superfície foliar exposta à luz solar. Dessa forma, o presente trabalho teve por objetivo a caracterização histológica da folha da espécie, visando compreender melhor esse mecanismo de resposta ao estresse hídrico. Para tanto foram realizados cortes transversais e paradérmicos da lâmina foliar, bem como, cortes transversais do pecíolo, sendo estes analisados e as imagens capturadas em microscópio de luz. Os resultados permitem, entre outras coisas, afirmar que E. glazioviania possui características tipicamente xerofíticas, sendo elas: cutícula espessa em ambas as superfícies, folha hipoestomática, com muitos tricomas tectores na face abaxial, além de uma característica que pode ser exclusiva da espécie e que possivelmente justifique tal resposta, a qual relaciona-se a presença de ductos glandulares, que percorrem toda a extensão do pecíolo, em continuidade com a lâmina foliar.In response to hydrous stress, the adaptive mechanisms with a potential adaptive value presented by Eugenia glazioviana Kiaersk is notable, whose leaf turgidity loss and the blade consequent curvature from the horizontal to vertical position, without the leaves abscission, are associated with the reduction of the leaf surface exposed to sunlight. This study aimed to characterize histological leaf species to better understand the mechanism in response to hidrous stress. Therefore, we performed transverse and paradermal cuts from the leaf blade and petiole cross-sections. They were analyzed and the images were captured under light microscope. Among other things, the results allowed to state that E. glazioviana has typically xerophytic characteristics, namely: thick cuticle on both surfaces, hypostomatic leaves with many trichomes on the abaxial side, and a characteristic that may be unique to that species and possibly justify such response, which is related to the glandular ducts presence, running the petiole length in continuity with the leaf blade

Microrganismos endofíticos e a cultura de tecidos vegetais: quebrando paradigmas

Plant tissue culture has been an important tool widely used for various purposes. Within this context, the term axenic plant has been taken as an ideal to be achieved in this technique, which the search based on methods that effectively eliminate any microorganisms that may eventually grow into the culture medium. However, it is seen that the conception of contamination in tissue culture should be reviewed as well as axenic plants, because several studies have shown that even in asymptomatic microplants considered axenic, there is an ubiquitous and that the endophytic community mostly plays a fundamental role in the establishment, development and acclimatization of cultures, therefore, beneficial microorganisms that should be preserved in vitro.A cultura de tecidos vegetais tem sido uma importante ferramenta amplamente utilizada para diversas finalidades. Neste contexto, o termo plantas axênicas, tem sido difundido como um ideal a ser atingido nesta técnica, havendo a busca de métodos que eliminem de forma eficaz todo e qualquer microrganismo que possa, eventualmente, crescer no meio de cultura. No entanto, cada vez mais se observa que a concepção de contaminação dentro da cultura de tecidos deve ser revista, assim como a de planta axênica, pois muitos trabalhos mostram que mesmo em microplantas assintomáticas consideradas axênicas, existe uma comunidade endofítica onipresente e que na sua grande maioria desempenha papel fundamental no estabelecimento, desenvolvimento e aclimatização das culturas, sendo, portanto, microrganismos benéficos que devem ser conservados no cultivo in vitro

Uso do Mapa Conceitual como Ferramenta Auxiliar no Ensino da Disciplina Política e Organização da Educação Brasileira

Os mapas conceituais consistem em uma representação gráfica e visual de idéias e da inter-relação entre idéias e/ou conceitos. Há uma série de usos para os mapas conceituais na escola e a partir disto desenvolveu-se a hipótese do uso do mapa conceitual como auxiliar no processo de ensino e aprendizagem do conteúdo da disciplina Política e Organização da Educação Brasileira ministrada para cursos de licenciatura de uma universidade pública localizada em Piracicaba/SP. Para tal, realizou-se a divisão dos 42 alunos matriculados na disciplina em duplas, para elaborar o mapa conceitual inicial, dispondo de 30 minutos após a aula. Os mapas foram recolhidos e corrigidos. Após a correção os mapas foram devolvidos aos alunos, que fizeram o mapa final, também em 30 minutos e depois de estudarem e pesquisarem sobre o tema. Os resultados do trabalho foram avaliados mediante a análise qualitativa e quantitativa dos mapas. Dessa forma verificou-se, entre outros resultados, que os mapas finais foram maiores, mais complexos e com mais ramificações quando comparados aos mapas iniciais. Concluiu-se que os mapas foram importantes na promoção do processo de ensino e aprendizagem, visto que os alunos tiveram melhor aproveitamento da disciplina e maior facilidade para resolução das provas

Blue-light filtering alters angiogenic signaling in human retinal pigmented epithelial cells culture model

Background: light exposure and more specifically the spectrum of blue light contribute to the oxidative stress in Age-related macular degeneration (AMD). The purpose of the study was to establish whether blue light filtering could modify proangiogenic signaling produced by retinal pigmented epithelial (RPE) cells under different conditions simulating risk factors for AMD. Methods: three experiments were carried out in order to expose ARPE-19 cells to white light for 48 h with and without blue light-blocking filters (BLF) in different conditions. In each experiment one group was exposed to light with no BLF protection, a second group was exposed to light with BLF protection, and a control group was not exposed to light. The ARPE-19 cells used in each experiment prior to light exposure were cultured for 24 h as follows: Experiment 1) Normoxia, Experiment 2) Hypoxia, and Experiment 3) Lutein supplemented media in normoxia. The media of all groups was harvested after light exposure for sandwich ELISA-based assays to quantify 10 pro-angiogenic cytokines. Results: a significant decrease in angiogenin secretion levels and a significant increase in bFGF were observed following light exposure, compared to dark conditions, in both normoxia and hypoxia conditions. With the addition of a blue light-blocking filter in normoxia, a significant increase in angiogenin levels was observed. Although statistical significance was not achieved, blue light filters reduce light-induced secretion of bFGF and VEGF to near normal levels. This trend is also observed when ARPE-19 cells are grown under hypoxic conditions and when pre-treated with lutein prior to exposure to experimental conditions. Conclusions: following light exposure, there is a decrease in angiogenin secretion by ARPE-19 cells, which was abrogated with a blue light - blocking filter. Our findings support the position that blue light filtering affects the secretion of angiogenic factors by retinal pigmented epithelial cells under normoxic, hypoxic, and lutein-pretreated conditions in a similar manner

Synthesis of thia-Michael-Type Adducts between Naphthoquinones and N-Acetyl-L-Cysteine and Their Biological Activity

A series of naphthoquinones, namely, 1,4-naphthoquinone, menadione, plumbagin, juglone, naphthazarin, and lawsone, were reacted with N-acetyl-L-cysteine, and except for lawsone, which did not react, the related adducts were obtained. After the tuning of the solvent and reaction conditions, the reaction products were isolated as almost pure from the complex reaction mixture via simple filtration and were fully characterized. Therefore, the aim of this work was to evaluate whether the antitumor activity of new compounds of 1,4-naphthoquinone derivatives leads to an increase in ROS in tumor cell lines of cervical carcinoma (HeLa), neuroblastoma (SH-SY5Y), and osteosarcoma (SaOS2, U2OS) and in normal dermal fibroblast (HDFa). The MTT assay was used to assay cell viability, the DCF-DA fluorescent probe to evaluate ROS induction, and cell-cycle analysis to measure the antiproliferative effect. Compounds 8, 9, and 12 showed a certain degree of cytotoxicity towards all the malignant cell lines tested, while compound 11 showed biological activity at higher IC50 values. Compounds 8 and 11 induced increases in ROS generation after 1 h of exposure, while after 48 h of treatment, only 8 induced an increase in ROS formation in HeLa cells. Cell-cycle analysis showed that compound 8 caused an increase in the number of G0/G1-phase cells in the HeLa experiment, while for the U2OS and SH-SY5Y cell lines, it led to an accumulation of S-phase cells. Therefore, these novel 1,4-naphthoquinone derivatives may be useful as antitumoral agents in the treatment of different cancers

Hybrid Image Visualization Tool for 3D integration of CT coronary anatomy and quantitative myocardial perfusion PET

Purpose: Multimodal cardiac imaging by CTA and quantitative PET enables acquisition of patient-specific coronary anatomy and absolute myocardial perfusion at rest and during stress. In the clinical setting, integration of this information is performed visually or using coronary arteries distribution models. We developed a new tool for CTA and quantitative PET integrated 3D visualization, exploiting XML and DICOM clinical standards. Methods: The Hybrid Image Tool (HIT) developed in the present study included four main modules: (1) volumetric registration for spatial matching of CTA and PET datasets, (2) an interface to PET quantitative analysis software, (3) a derived DICOM generator able to build DICOM dataset from quantitative polar maps, and (4) a 3D visualization tool of integrated anatomical and quantitative flow information. The four modules incorporated in the HIT tool communicate by defined standard XML files: XML-transformation and XML MIST standards. Results: The HIT tool implements a 3D representation of CTA showing real coronary anatomy fused to PET derived quantitative myocardial blood flow distribution. The technique was validated on 16 datasets from EVINCI study population. The validation of the method confirmed the high matching between "original" and derived datasets as well as the accuracy of the registration procedure. Conclusions: Three-dimensional integration of patient-specific coronary artery anatomy provided by CTA and quantitative myocardial blood flow obtained from PET imaging can improve cardiac disease assessment. The HIT tool introduced in this paper may represent a significant advancement in the clinical use of this multimodal approach

The acceptability of vaginal smear self-collection for screening for cervical cancer: a systematic review

Cervical cancer is a major cause of death in adult women. However, many women do not undergo cervical cancer screening for the following reasons: fear, shame, physical limitations, cultural or religious considerations and lack of access to health care services. Self-collected vaginal smears maybe an alternative means of including more women in cervical cancer screening programs. The objective of this systematic review was to evaluate the acceptability of vaginal smear self-collection for cervical cancer screening. We selected articles from PubMed, the Cochrane Library and Embase that were published between January 1995 and April 2016. Studies written in English, French, Italian, Portuguese or Spanish that involved women between 18 and 69 years of age who had engaged in sexual intercourse were included in this review. The review was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Nineteen studies were ultimately evaluated in this review. Most of the included studies (n=17) demonstrated that the self-collection method exhibited outstanding acceptability among women with respect to cervical cancer screening, and only two studies indicated that self-collection exhibited low acceptability among women in this context. The acceptability of self-collection was determined subjectively (without standardized questionnaires) in 10 studies (53%) and via structured and validated questionnaires in the remaining studies. The results of our review suggest that the self-collection method is well-accepted and may therefore encourage greater participation in cervical cancer screening programs. However, additional studies are required to verify these results

Comparability of Hot-Wire Estimates of Liquid Water Content in SLD Conditions

Future compliance to FAA 14 CFR Part 25 and EASA CS-25 Appendix O conditions has required icing wind tunnels to expand their cloud simulation envelope, and demonstrate accurate calibration of liquid water content and droplet particle size distributions under these conditions. This has led to a renewed community interest in the accuracy of these calibrations, and the potential inter-facility bias due to the choice of instrumentation and processing methods. This article provides a comparison of the response of various hot-wire liquid water content instruments under Appendix C and supercooled large droplet conditions, after an independent similar analysis at other wind tunnel facilities. The instruments are being used, or are under consideration for use, by facilities collaborating in the ICE GENESIS program. For droplet median volume diameters (MVDs) between about 15 and 250 micrometer, cylindrical hot wire LWC sensors were found to consistently and increasingly under-read measurements from conical and trough TWC sensors as MVD increased, and were not considered further. Of the remaining TWC sensors, the specific instruments investigated were found to agree within about 20% of their average test point response for the range of conditions tested, but systematic scale differences between instruments were found to reach about a factor of 1.4. Sensitivity to increasing droplet MVD was concluded to be similar amongst different instruments given the uncertainties, except for two that exhibited notable roll-off with MVD relative to the others

Electric properties of dust devils

Dust devils are one of the most effective phenomena able to inject dust grains into the atmosphere. On Mars, they play an important role to maintain the haze and can significantly affect the global dust loading, especially outside the dust storm season. Despite dust devils having been studied for a century and a half, many open questions regarding their physics still exist. In particular, the nature of the dust lifting mechanisms inside the vortices, the development of the induced electric field and the exact contribution to the global atmospheric dust budget are still debated topics. In this paper, we analyze the dust devil activity observed in the Moroccan Sahara desert during a 2014 field campaign. We have acquired the most comprehensive field data set presently available for the dust devils: including meteorological, atmospheric electric field and lifted dust concentration measurements. We focus our attention on the electric field induced by vortices, using this as the principal detection parameter. We present, for the first time, the statistical distribution of dust devil electric field and its relationships with the pressure drop, the horizontal and vertical vortex velocity and the total dust mass lifted. We also compare the pressure drop distribution of our sample with the ones observed on the martian surface showing the similarity of the dust devils samples and the usefulness of this study for the next martian surface missions