4,381 research outputs found

    The Major Facilitator Superfamily Transporter ZIFL2 Modulates Cesium and Potassium Homeostasis in Arabidopsis

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    Potassium (K(+)) is an essential mineral nutrient for plant growth and development, with numerous membrane transporters and channels having been implicated in the maintenance and regulation of its homeostasis. The cation cesium (Cs(+)) is toxic for plants but shares similar chemical properties to the K(+) ion and hence competes with its transport. Here, we report that K(+) and Cs(+) homeostasis in Arabidopsis thaliana also requires the action of ZIFL2 (Zinc-Induced Facilitator-Like 2), a member of the Major Facilitator Superfamily (MFS) of membrane transporters. We show that the Arabidopsis ZIFL2 is a functional transporter able to mediate K(+) and Cs(+) influx when heterologously expressed in yeast. Promoter-reporter, reverse transcription-PCR and fluorescent protein fusion experiments indicate that the predominant ZIFL2.1 isoform is targeted to the plasma membrane of endodermal and pericyle root cells. ZIFL2 loss of function and overexpression exacerbate and alleviate plant sensitivity, respectively, upon Cs(+) and excess K(+) supply, also influencing Cs(+) whole-plant partitioning. We propose that the activity of this Arabidopsis MFS carrier promotes cellular K(+) efflux in the root, thereby restricting Cs(+)/K(+) xylem loading and subsequent root to shoot translocation under conditions of Cs(+) or high K(+) external supply.FCT fellowships: (SFRH/BPD/44640/2008, SFRH/BPD/81221/2011)

    Eficiência de Metarhizium anisopliae (Metsch) sorokin no controle de cigarrinhas-das-pastagens (Hemiptera: Cercopidae) em Brachiaria bryzantha em Rondônia-Brasil.

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    O objetivo desta pesquisa foi avaliar a eficiência de Metarhizium anisopliae (isolado ESALQ 1037) em diferentes formulações, dosagens de conídeos e número de aplicações no controle da cigarrinha-das-pastagens, conduzida em ensaio de campo em pastagem de capim-Marandu (Brachiaria bryzantha), no Município de Corumbiara, RO, no período de dezembro de 2007 a fevereiro de 2008. O isolado foi aplicado a partir das 17h, sob temperatura média de 18° C e umidade relativa de 69%. O volume de calda utilizado foi de 300 L/ ha-1, utilizando-se pulverizador a CO². As doses aplicadas foram de 0,5 x109, 1 x109, 2 x109 conídios viáveis/ha-1, com vazão de 300 litros/ha-1. As avaliações procederam-se aos 0, 15, 32, 45, 61 e 75 dias, sendo uma antes das aplicações, e cinco após as aplicações do entomopatógeno, contando-se as cigarrinhas (ninfas) por ponto de 0,0625 m² (quadrado de 0,25 m x 0,25 m). Aos 0 dias a infestação era de 153,6 ninfas/ m². Foi observado que os níveis de ninfas diminuíram com a aplicação de M. anisopliae em todos os tratamentos. Pelos resultados obtidos, o tratamento mais eficiente foi o Metarril SC 2 x109 conídios viáveis/ha-1, na formulação de óleo emulsionável, com duas aplicações (94,19%). Conclui-se que, o M. anisopliae (ESALQ 1037) constitui-se em uma alternativa promissora para o manejo integrado das cigarrinhaspastagens em capim-Marandu (B. brizantha) para a Agricultura Familiar em Rondônia

    Expressão comportamental das diferenças sexuais no campo aberto e na atividade da colinesterase plasmática de ratos machos, fêmeas e fêmeas masculinizadas

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    Sexual differences in behaviour and metabolism are well recognized. While some of these differences are related to testosterone exposure during neonatal life, others do not depend on the organizational action of androgens during early development. The objective of the following experiments was to study the development of sexual differences in plasma cholinesterase activity and to determine if these differences were related to testosterone exposure postnatally. Open-field activity was also recorded as a behavioral indicator of the actions of testosterone on sexual differentiation of the central nervous system. Three treatment groups of animals were used: normal male, normal female, and masculinized female rats (1 mg testosterone, SC, on day 2 of postnatal life). Open-field behaviour was measured on three consecutive days just after weaning (21 -23 days of age), in association with the onset of puberty (30 - 36 days of age), or as adults (90 - 110 days of age); plasma cholinesterase activity was measured at 22, 30 - 36, and 90 - 110 days of age. As expected a sex difference in open-field activity was found between normal males and females. Postnatal androgen treatment in females decreased open-field activity in adulthood to levels similar to those found in normal males. Similar differences were observed just after weaning, but not at 30-36 days of age. In contrast, significant differences in cholinesterase activity were observed in adult animals, but not at days 22 and 30 - 33 of age. Masculinized female rats showed no differences in plasma cholinesterase activity when compared to normal female rats, both groups differing from males. These data suggest that sexual differences in plasma cholinesterase activity in adult rats, unlike differences in open-field behaviour, are not dependent on testosterone exposure during postnatal life. In addition, the results have shown that under stress (weaning) sex differences in open-field behaviour can be observed as early as at 21 -23 days of age.Sabe-se que algumas diferenças sexuais no metabolismo e no comportamento estão relacionadas com o efeito neonatal da testosterona e outras não sofrem esse tipo de influência. O objetivo desses experimentos foi estudar o desenvolvimento das diferenças sexuais na atividade da colinesterase plasmática e de determinar se essas diferenças seriam relacionadas com a exposição pós-natal à testosterona em ratos. A atividade geral no campo aberto foi também verificada como um indicador comportamental das ações da testosterona na diferenciação sexual do sistema nervoso central. Foram usados três grupos de animais: machos normais, fêmeas normais e fêmeas masculinizadas (1 mg testosterona. SC, no 2º. dia de vida pós-natal). A atividade geral no campo aberto foi medida durante três dias consecutivos logo após o desmame (21 - 23 dias de idade), durante o início da puberdade (30 - 36 dias de idade) e nos adultos (90 - 110 dias de idade); a atividade da colinesterase plasmática foi medida aos 22, 30 - 36 e 90 - 110 dias de idade. Como esperado, foi encontrada uma diferença sexual no campo aberto entre machos e fêmeas normais. O tratamento pós-natal com andrógeno nas fêmeas diminuiu a atividade no campo aberto na idade adulta a padrões similares àqueles observados para machos normais. Foram observadas diferenças similares logo após o desmame, mas não aos 22 e aos 30 - 36 dias de idade. Em contraste, foram observadas diferenças significantes na atividade da colinesterase de animais adultos mas não nos dias 22 e 30 - 33 de idade. Quando comparadas às fêmeas normais, as fêmeas masculinizadas não apresentaram diferenças na atividade da colinesterase plasmática, sendo que esses dois grupos foram diferentes dos machos. Esses resultados sugerem que as diferenças sexuais na atividade da colinesterase plasmática de ratos adultos não são dependentes de exposição a testosterona durante o início da vida pós-natal. Além disso os resultados demonstram que sob estresse (desmame) as diferenças sexuais no comportamento no campo aberto podem ser observadas já aos 21-23 dias de idade

    Hydrogen sulfide donors alleviate itch secondary to the activation of type-2 protease activated receptors (PAR-2) in mice.

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    Published onlineJOURNAL ARTICLEHydrogen sulfide (H2S) has been highlighted as an endogenous signaling molecule and we have previously found that it can inhibit histamine-mediated itching. Pruritus is the most common symptom of cutaneous diseases and anti-histamines are the usual treatment; however, anti-histamine-resistant pruritus is common in some clinical settings. In this way, the involvement of mediators other than histamine in the context of pruritus requires new therapeutic targets. Considering that the activation of proteinase-activated receptor 2 (PAR-2) is involved in pruritus both in rodents and humans, in this study we investigated the effect of H2S donors on the acute scratching behavior mediated by PAR-2 activation in mice, as well as some of the possible pharmacological mechanisms involved. The intradermal injection of the PAR-2 peptide agonist SLIGRL-NH2 (8-80nmol) caused a dose-dependent scratching that was unaffected by intraperitoneal pre-treatment with the histamine H1 antagonist pyrilamine (30mg/kg). Co-injection of SLIGRL-NH2 (40nmol) with either the slow-release H2S donor GYY4137 (1 and 3nmol) or the spontaneous donor NaHS (1 and 0.3nmol) significantly reduced pruritus. Co-treatment with the KATP channel blocker glibenclamide (200nmol) or the nitric oxide (NO) donor sodium nitroprusside (10nmol) abolished the antipruritic effects of NaHS; however, the specific soluble guanylyl cyclase inhibitor ODQ (30μg) had no significant effects. The transient receptor potential ankyrin type 1 (TRPA1) antagonist HC-030031 (20μg) significantly reduced SLIGRL-NH2-induced pruritus; however pruritus induced by the TRPA1 agonist AITC (1000nmol) was unaffected by NaHS. Based on these data, we conclude that pruritus secondary to PAR-2 activation can be reduced by H2S, which acts through KATP channel opening and involves NO in a cyclic guanosine monophosphate (cGMP)-independent manner. Furthermore, TRPA1 receptors mediate the pruritus induced by activation of PAR-2, but H2S does not interfere with this pathway. These results provide additional support for the development of new therapeutical alternatives, mainly intended for treatment of pruritus in patients unresponsive to anti-histamines.MNM and SKPC are recipients of fellowships from the National Council for Scientific and Technological Development (CNPq) and grants from the Sao Paulo Research Foundation (FAPESP). RT, MW and MEW would like to thank the Brian Ridge Scholarship for its support (RT)

    Semantic Web Services for Multi-Agent Systems Interoperability

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    Agent-based technologies are often used including existing web services. The outputs of some services are also frequently used as inputs for other services, including other MAS. However, while agent-based technologies can be used to provide services, these are not described using the same semantic web technologies web services use, which makes it difficult to discover, invoke and compose them with web services seamlessly. In this paper, we analyse different agent-based technologies and how these can be described using extensions to OWL-S. Additionally, we propose an architecture that facilitates these services’ usage, where services of any kind can be registered and executed (semi-)automatically.The present work has been developed under the PIANISM Project (ANI|P2020 40125) and has received funding from FEDER Funds through NORTE2020 program and from National Funds through Fundação para a Ciência e a Tecnologia (FCT) under the project UID/EEA/00760/2019. Gabriel Santos is supported by national funds through FCT PhD studentship with reference SFRH/BD/118487/2016.info:eu-repo/semantics/publishedVersio

    Are the Health Information Systems (HIS) ready for the digital transformation? Challenges and future perspectives for HIS in Portugal

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    The relevance of Health Information Systems (HIS) lies in the impact of these systems have on the citizen, on public health, and on sustainability and preparedness in the future, in terms of health. The recent pandemic situation, caused by COVID-19, has highlighted the importance of HIS, particularly in the practice of medicine. However, despite all the technology that enables HIS development, its materialization requires intervention at the strategic, political, technological, and also sociocultural level. This paper aims to reflect on the challenges of HIS, at a time when technologies enable the creation of new approaches and models for care delivery, as well as identify scenarios that may characterize this practice in the future. For this purpose, an empirical study was conducted, based on interviews. The results point to the existence of emerging technologies that can promote the development of HIS focused on to \u27health and well-being\u27 following a preventive model approach

    Protective effects of exogenous and endogenous hydrogen sulfide in mast cell-mediated pruritus and cutaneous acute inflammation in mice.

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    Published onlineJournal ArticleThis is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.The recently described 'gasomediator' hydrogen sulfide (H2S) has been involved in pain mechanisms, but its effect on pruritus, a sensory modality that similarly to pain acts as a protective mechanism, is poorly known and controversial. The effects of the slow-releasing (GYY4137) and spontaneous H2S donors (Na2S and Lawesson's reagent, LR) were evaluated in histamine and compound 48/80 (C48/80)-dependent dorsal skin pruritus and inflammation in male BALB/c mice. Animals were intradermally (i.d.) injected with C48/80 (3μg/site) or histamine (1μmol/site) alone or co-injected with Na2S, LR or GYY4137 (within the 0.3-100nmol range). The involvement of endogenous H2S and KATP channel-dependent mechanism were also evaluated. Pruritus was assessed by the number of scratching bouts, whilst skin inflammation was evaluated by the extravascular accumulation of intravenously injected (125)I-albumin (plasma extravasation) and myeloperoxidase (MPO) activity (neutrophil recruitment). Histamine or C48/80 significantly evoked itching behavior paralleled by plasma extravasation and increased MPO activity. Na2S and LR significantly ameliorated histamine or C48/80-induced pruritus and inflammation, although these effects were less pronounced or absent with GYY4137. Inhibition of endogenous H2S synthesis exacerbated C48/80-induced responses, whereas the blockade of KATP channels by glibenclamide did not. High-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) revealed that Na2S and LR, but not GYY4137, significantly attenuated C48/80-induced histamine release from rat peritoneal mast cell in vitro. We provide first evidences that H2S exerted protective effect against acute pruritus mediated via histaminergic pathways in murine skin, thus making of H2S donors a potential alternative/complementary therapy for treatment of acute pruritus.Sao Paulo Research Foundation (Fapesp grant numbers: 2013/04.151-3, 2014/15.576-8, 2014/24.518-1) and CNPq (grant number: 163278/2012-1). GDN, MNM and SKPC are recipients of fellowships from the National Council for Scientific and Technological Development (CNPq). We thank Irene M Gouvea, Flávia B de Lira and Mauro Sucupira for their techinical support
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