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Pseudomonas syringae is a phytopathogenic bacterium that causes lesions in leaves during the colonisation process. The damage is associated with production of many virulence factors, such as biofilm and phytotoxins. The essential oils of Thymus vulgaris (thyme) and Origanum vulgare (oregano) have been demonstrated to inhibit P. syringae. The aim of this study was to investigate the effects of T. vulgaris and O. vulgare essential oils on production of virulence factors of phytopathogenic P. syringae strains, including anti-biofilm and anti-toxins activities. The broth microdilution method was used for determination of MIC and biofilm inhibition assays. Coronatine, syringomycin and tabtoxin were pheno- and genotypically evaluated. Both oils showed good inhibitory activity against P. syringae, with MIC values from 1.43 to 11.5 mg·ml-1 for thyme and 5.8 to 11.6 mg·ml-1 for oregano. Biofilm formation, production of coronatine, syringomycin and tabtoxin were inhibited by thyme and oregano essential oil in most strains. The results presented here are promising, demonstrating the bactericidal activity and reduction of virulence factor production after treatment with thyme and oregano oil, providing insight into how they exert their antibacterial activity. These natural products could be considered in the future for the control of diseases caused by P. syringae.

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This review present a critical comparison of the electrochemical behavior and analytical performance of glassy carbon electrodes (GCE) modified with carbon nanotubes (CNTs) dispersed in different polymers: polyethylenimine (PEI), PEI functionalized with dopamine (PEI-Do), polyhistidine (Polyhis), polylysine (Polylys), glucose oxidase (GOx) and double stranded calf-thymus DNA (dsDNA). The comparison is focused on the analysis of the influence of the sonication time, solvent, polymer/CNT ratio, and nature of the polymer on the efficiency of the dispersions and on the electrochemical behavior of the resulting modified electrodes. The results allow to conclude that an adequate selection of the polymers makes possible not only an efficient dispersion of CNTs but also, and even more important, the building of successful analytical platforms for the detection of different bioanalytes like NADH, glucose, DNA and dopamine.

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PURPOSE: To determine whether shear forces applied to the corneal epithelium by the repeated insertion and removal of a hydrogel contact lens alter the size and number of cells removed and to determine the contribution of apoptosis to this process. METHODS; Human corneal cells were collected from eight healthy subjects by sequential contact lens cytology (20 lens insertions and removals). Collected cells were stained with acridine orange for counting and measurement of cell size. In a separate experiment, collected cells were fixed and stained with TdT-mediated dUTP nick-end labeling (TUNEL) or labeled immediately after collection using annexin V. Hoechst stain and propidium iodide (PI) were used as nuclear counterstains. The proportion of cells labeled with acridine orange, TUNEL, and annexin V was quantified by fluorescence microscopy. RESULTS; The number of cells increased in later collections, and cells were smaller. The mean number of positively stained cells using TUNEL was 57%. Annexin V labeling on unfixed fresh samples showed a mean of 64%, with an increase in later collections. Apoptotic bodies were observed in very few cells. In most cells the nucleus and cytoplasmic membrane were intact. Structures were observed in which nuclei were missing (Hoechst negative) but in which cytoplasm had the size and appearance of whole, nucleated cells. These structures (cell ghosts) increased in number along with the increase in nucleated cells in later collections. CONCLUSIONS: The sequential removal of a soft contact lens caused a progressive increase in the number of cells collected from the surface and a progressive decrease in their size. The majority of nucleated cells removed by a contact lens were apoptotic in the sense of being positively labeled by TUNEL and annexin V. Morphologically they differed from classically apoptotic cells, in that cells showed an intact nuclear structure and no discernible apoptotic bodies. They could represent a last stage in a pathway of cell differentiation in which frictional forces induced by the removal of the contact lens activate the apoptotic program and cause the cell to be shed. There is also a pathway in which cells lose their nuclei before leaving the epithelial surface.

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Twenty-six compounds have been identified from fresh orange airborne volatiles, the most abundant being limonene and alloaromadendrene. Ethyl- and butylhexanoates were found in middle concentrations, whereas the other compounds occur at low levels. Electroantennograms recorded fromCeratitis capitata Wied. (males and females) revealed limonene. butyl hexanoate, dihydrocarvone, and limonene oxide to be most active. In the case of dihydrocarvone, 4-ethyl acetophenone, and carvone, female antennae give greater responses than antennae of males. Limonene oxide was more active for males than females. Total airborne volatiles recovered from oranges elicited high EAGs, with females being more sensitive than males.

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Descreve atividades, problemas e resultados observados, por uma equipe multiprofissional no desenvolvimento de um projeto de educaçäo em saúde sobre a temática AIDS, junto aos alunos e professores de uma escola pública de primeiro grau. Mostra que a efetiva integraçäo entre profissionais das áreas de Saúde e Educaçäo permite a viabilizaçäo deste tipo de proposta, mesmo tratando de temas considerados tabu, o que dificulta ou até impede a sua abordagem junto aos alunos

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Descreve trabalho de educaçäo em saúde escolar realizado numa escola de 1§ grau da Rede Estadual de Ensino no Butantä onde pais, alunos e professores foram envolvidos em um processo de ensino-aprendizagem relacionado a três temas principais (adaptaçäo da criança a escola, morbidade do escolar, higiene pessoal e do ambiente físico). Analisa metodologia utilizada ressaltando sua importância no processo de desenvolvimento comunitário

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The search for Salmonella spp in the faeces and of Staphylococcus aureus in pharyngeal pads during examinations for the renewal of the Medical Fitness Booklet, leads to a number of considerations of a technical-health and economic nature. Whereas the identification of Staphylococcus aureus is fairly straightforward, that of salmonella in the faeces is not so easy. Doubtful results are commonplace and bacteria are often found with features similar to salmonella; this means extra examinations with commitment of time, money etc.

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Nine primary myxedematous patients were subjected to all-night polysomnographic recordings under the following conditions: (1) basal or myxedematous state; (2) acute replacement therapy (treatment with thyroid hormones at doses that increased weekly to the maximal replacement dose, Mrd); and (3) chronic replacement therapy (maintenance on the Mrd; euthyroid state). The most striking abnormality found in the sleep pattern during the myxedematous state was observed in both young adult (greater than 20 years old) and adult (greater than 50 years old) patients, consisting of either a complete absence or very low levels of slow wave sleep (SWS). Replacement therapy was accompanied by a restoration of the normal sleep pattern in 3 of the 4 patients that were followed. In contrast, younger patients (14-18 years old with a bone age of less than or equal to 10 years) had normal levels of SWS, with the exception of an adolescent with a bone age of less than 3 years. The latency for rapid eye movement (REM) sleep tended to increase during acute replacement therapy and became normal when euthyroidism was reached. These results lend support to the proposal that thyroid hormones exert central effects on the adult CNS.

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The incidence of sleep-related breathing disorders (SRBDs) associated with hemoglobin desaturation was determined by nocturnal polygraphic evaluations in 26 healthy men, aged 55-70 years. Sixteen subjects (62%) had abnormal rates of at least 12 episodes per hour of sleep: 8 had occlusive, and 8 had central apnea or hypopnea. During waking ten of 16 SRBD subjects and only one subject without SRBDs exhibited either an elevated nasopharyngeal airway resistance (n = 4) or a reduced ventilatory response to hypercapnia (n = 4) and/or hypoxia (n = 3). However, these abnormalities were not related to the type or severity of SRBDs, and 6 subjects with SRBDs demonstrated no respiratory defect. We conclude that SRBDs have a very high incidence in older males and are not usually secondary to pulmonary cardiac, neurological, or behavioral disorders. Additionally, we hypothesize that abnormalities in ventilatory control or upper airway resistance contribute to SRBDs, but depression of brain stem reticular formation activity during sleep plays a primary role in these disorders. Factors related to both aging and SRBDs are reviewed. These include reduced chemoreceptor responses, altered steroid hormone metabolism, and use and metabolism of hypnotic drugs and alcohol.

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Average pesticide residue levels were determined for the 17 main food groups in the average Spanish diet. Using these levels and the estimated average intake of these foods, authors computed an individual's average daily consumption of pesticides from each of these food groups and her/his total diet. Foods were acquired over a 1-year period from the market of Valencia, a city that gets supplies from an agricultural area where pesticide consumption is appreciably higher than that of the rest of the country. Thus average residue levels found must be higher than the national average. Except for fruits and vegetables, the different items composing each food group were sampled in proportion to the amount consumed in the average Spanish diet. Foods forming each group were homogenized into composite samples. All foods were analyzed raw. The most frequently detected pesticides were DDT and BHC. Malathion was detected at levels less than 0.10 ppm in some samples of vegetable oils, pears, and apples. DDT and BHC levels varied from undetectable to amounts less than 1.0 ppm. Highest levels were found in lard. An individual's average daily intake of pesticides was calculated to be 78 mug DDT, a sum which includes residues of o,p'-DDT, p,p'-DDT, and p,p'-DDE, and 13.8 mug gamma-BHC. These levels are much lower than the maximum acceptable daily limits established by the United Nations Food Agricultural Organization and World Health Organization.

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