333 research outputs found

    Mediterranean sea cliff plants: morphological and physiological responses to environmental conditions

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    Aims The plants of Mediterranean sea cliff ecosystems are resistant to several environmental challenges. In the present study, six species typical of the coastal rocky cliffs have been analysed in order to evaluate their diverse morphological and physiological responses to their environment across the seasons, and to examine the strategy of the ecological group to which each species belongs. Since these species are widespread across the Mediterranean region, our aim was also to highlight their ecophysiological features in habitats where the direct influence of the sea is stronger. Methods The selected species are characteristic of the sea cliffs of Elba island (Tyrrhenian sea, Italy): the halophyte Crithmum maritimum, the semideciduous Helichrysum italicum and Lavandula stoechas, and the sclerophylls Myrtus communis, Quercus ilex and Rhamnus alaternus. Four morphological traits - canopy height, leaf area, specific leaf area and leaf dry matter content - and two physiological traits - leaf water potential (LWP) and photosynthetic efficiency (PE), measured before the dawn and at midday were analysed. Water potential was measured by a pressure chamber and photosynthetic efficiency was determined by the analysis of chlorophyll fluorescence. Plant performance was also evaluated by calculating chronic (PIchr) and dynamic photoinhibition (PIdyn). Important findings Crithmum maritimum showed high resistance to the recurrent dry periods, because of the high water storage capacity of its leaves and its PE declined markedly only in July, under the harshest climatic conditions. Semideciduous taxa utilise primarily an avoidance strategy, which aims at reducing the overall leaf surface, while sclerophylls mostly show a tolerance strategy towards the prevailing stressors, as demonstrated by LWP and PE, that are lower in the sclerophylls than in the semideciduous taxa during summer, due to osmoregulation and photoinhibition, respectively. Furthermore, variability of physiological parameters was higher in the sclerophylls than in the semideciduous taxa, because the former had to withstand wider oscillations of their LWP and PE. The sclerophyllous taxa underwent a slight loss of PE also in winter, likely owing to the combined action of low temperature and high irradiance. In Mediterranean sea cliff ecosystems, the stressful combination of high irradiance, high temperatures and low rainfall typical of the summer season may have been intensified by the shallow soil which displays a poor water storage capacity. On the other hand, winter stress, caused by high solar radiation and low temperatures, does not seem to seriously affect the performance of the studied species

    Encartes especiais: a gestão do conflito entre publicidade e produção gráfica

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    Na contemporaneidade, a relação entre tempo e espaço, sociedade e trabalho, sofreu grandes transformações. A integração dessas mudanças foi acompanhada por novos processos de homologação dos modelos de consumo e de produção. O objetivo deste artigo é demonstrar como podemos utilizar a comunicação, nesses novos modelos, para melhoraro entendimento entre departamentos e pessoas, promovendo maior informação, conhecimento e, consequentemente,contribuindo para o trabalho coletivo, ao minimizar conflitos, desentendimentos e oposição de interesses. A minha monografia apresentada na banca do curso de Gestão da Comunicação, do departamento de Comunicações e Artes da ECA/USP, sobre o tema Encartes especiais: a gestão do conflito entre publicidade e produção gráfica na mídia impressa da Editora Abril, demonstra na prática as questões citadas.In contemporary times, the relationship between, time/space, society and work have undergone great changes. The integration of these changes was accompanied by new processes of approval of consumer and production patterns. The objective of this article is to demonstrate how we can use communication, these models, to improve the understanding between people and departments, promoting greater information, knowledge and, consequently, contributing to collective work, minimizing conflicts, discords and opposition interests. My paper was presented to a panel of Management of Communication of the ECA/USP about the theme Special Inserts – managing the conflict between production and graphic advertising in printed media of Abril Publisher demonstrates in practice the questions above

    Nitric Oxide And Hydrogen Peroxide Involvement During Programmed Cell Death Of Sechium Edule Sw. Nucellus

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    The nucellus is a maternal tissue that feeds the developing embryo and the secondary endosperm. During seed development the cells of the nucellus suffer a degenerative process early after fertilization as the cellular endosperm expands and accumulates reserves. Nucellar cell degeneration has been characterized as a form of developmentally programmed cell death (PCD). In this work we show that nucellus PCD is accompanied by a considerable production of both nitric oxide and hydrogen peroxide (NO and H(2)O(2)). Interestingly, each of the two molecules is able to induce the production of the other and to cause cell death when applied to a living nucellus. We show that the induced cell death has features of a PCD, accompanied by profound changes in the morphology of the nuclei and by a massive degradation of nuclear DNA. Moreover, we report that NO and H(2)O(2) cause an induction of caspase-like proteases previously characterized in physiological nucellar PCD. Document Type: Articl

    The involvement of indole-3-acetic acid in the control of stem elongation in dark- and lightgrown pea (Pisum sativum) seedlings

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    We investigated the role of auxin on stem elongation in pea (Pisum sativum L.) grown for 10 d in continuous darkness or under low-irradiance blue, red, far red and white light. The third internode of treated seedlings was peeled and the tissues (epidermis and cortex+central cylinder) were separately analyzed for the concentration of free and conjugated indole-3-acetic acid (IAA). Under red, far red and white light internode elongation was linearly related with the free IAA content of all internode tissues, suggesting that phytochrome-dependent inhibition of stem growth may be mediated by a decrease of free IAA levels in pea seedlings. The correlation between IAA and internode elongation, however, did not hold for blue light-grown seedlings. The hypothesis that the growth response under low-irradiance blue light might be correlated with the lack of phytochrome B signalling and changes in gibberellin metabolism is discussed in view of current knowledge on hormonal control of stem growth

    Gibberellins modulate auxin responses during tomato (Solanum lycopersicum L.) fruit development

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    In tomato, auxin and gibberellins (GAs) interact with each other to drive fruit growth and development. While the role of auxin in directing GA biosynthesis and signal is already known, very little information has been obtained about GA-mediated control of auxin signalling and response. Interestingly, we show that gibberellic acid (GA 3 ) is able to modify the expression of several auxin signalling genes in the partial auxin-insensitive diageotropica (dgt) mutant, suggesting that GAs may override the control of DGT on auxin signal. Procera (pro) mutation, which confers a constitutively active GA signal, enhances the effects of exogenous auxin, indicating that PRO may act as a negative effector of auxin responses in fruits. Indeed, transcript modulation of some auxin/indole acetic acid and auxin response factor genes in auxin-treated dgt/pro fruits suggests that PRO controls their expression possibly bypassing DGT. It was also shown that GA biosynthesis, in response to auxin treatment, is largely controlled by DGT. It is therefore conceivable that the DGT-mediated increase of active GAs in auxin-treated or pollinated fruits would promote PRO degradation, which in turn activates part of the auxin signalling cascade.Fil: Mignolli, Francesco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Vidoz, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Picciarelli, Piero. Università degli Studi di Pisa; ItaliaFil: Mariotti, Lorenzo. Università degli Studi di Pisa; Itali

    Gibberellins in Suspensors of Phaseolus coccineus

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    Hepatic necrosis associated with drug-induced hypersensitivity syndrome

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    Drug-induced hypersensitivity syndrome (DIHS; also known as drug reaction with eosinophilia and systemic symptoms [DRESS]) is a life-threatening condition first described by Chaikenetal. in 1950. It is characterized by extensive mucocutaneous rash; fever; lymphadenopathy; hepatitis; hematological abnormalities; damage to several organs such as kidney, heart, lungs, and pancreas; and possible reactivation of human herpesvirus-6 (HHV-6) or other herpes virus. Rare and severe cases may present hepatic necrosis, and about 15% of them result in death or liver transplantation. A hallmark of this syndrome is the late onset of symptoms after the drug exposure. The most common culprit drugs are the aromatic anticonvulsants (in almost 30% of the cases) and the antibiotics (which in some series represent 20% of the cases). The authors report a case of a 41-year-old female who presented to the emergency department with erythroderma, acute hepatitis, acute pancreatitis and acute renal failure, and was then treated with corticosteroid after the diagnosis of DIHS/DRESS. A specific culprit drug could not confidently be determined due to the presence of multiple drugs used by the patient. The clinical and laboratory outcome was apparently satisfactory, but unexpectedly, on the sixth day of hospitalization, the patient complained of nonspecific malaise, drowsiness, which progressed in a few hours with signs and symptoms of hepatic failure, refractory shock, and death. The autopsy findings showed submassive hepatic necrosis, and the immediate cause of death was attributed to hepatic failure

    Wharton’s jelly absence: a possible cause of stillbirth

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    The umbilical cord is a structure that provides vascular flow between the fetus \ud and the placenta. It contains two arteries and one vein, which are surrounded \ud and supported by gelatinous tissue known as Wharton’s jelly. There are many \ud umbilical cord abnormalities that are related to the prognosis of fetus survival \ud and birth weight. The authors report a case of umbilical cord constriction due to \ud the localized absence of Wharton’s jelly, which was undiagnosed antenatally \ud and had a fatal outcome. A review of the association between the absence of \ud Wharton’s jelly and an unfavorable pregnancy outcome was undertaken

    Blood flow velocity in monocular retinoblastoma assessed by color doppler

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    OBJECTIVE: To analyze the flow of retrobulbar vessels in retinoblastoma by color Doppler imaging. METHODS: A prospective study of monocular retinoblastoma treated by enucleation between 2010 and 2014. The examination comprised fundoscopy, magnetic resonance imaging, ultrasonography and color Doppler imaging. The peak blood velocities in the central retinal artery and central retinal vein of tumor-containing eyes (tuCRAv and tuCRVv, respectively) were assessed. The velocities were compared with those for normal eyes (nlCRAv and nlCRVv) and correlated with clinical and pathological findings. Tumor dimensions in the pathological sections were compared with those in magnetic resonance imaging and ultrasonography and were correlated with tuCRAv and tuCRVv. In tumor-containing eyes, the resistivity index in the central retinal artery and the pulse index in the central retinal vein were studied in relation to all variables. RESULTS: Eighteen patients were included. Comparisons between tuCRAv and nlCRAv and between tuCRVv and nlCRVv revealed higher velocities in tumor-containing eyes (

    Mucinous adenocarcinona of the appendix

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    Diagnosis of malignancy in the vermiform appendix is quite rare. The most common histological malignant neoplasia found in this tiny portion of the gastrointestinal tract is represented by the mucinous adenocarcinoma. This entity predominates in males around 50 years of age, and clinical presentation usually mimics or occurs along with an acute appendicitis. Early diagnosis is outside the rule since most cases at this stage are symptomless. The authors present the case of a 59-year-old female patient who looked for medical attention complaining of abdominal pain. Physical examination and laboratory workup were poor in diagnostic findings. The computed tomography images were compatible with the diagnosis of appendicitis and/or appendiceal neoplasia. The patient underwent a laparotomy and right hemicolectomy. The histological examination disclosed a moderately differentiated mucinous adenocarcinoma of the appendix stage T4a, N0, M0. The patient outcome was uneventful and was referred to an oncological center
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