243 research outputs found
Research information management at ISCTE-IUL: the library’s role
ISCTE-IUL is a Portuguese public university with approximately 9000 students enrolled in undergraduate (46%) and postgraduate (54%) programs. The Repository of ISCTE-IUL is running since 2007 sustained by an Open Access Policy approved in the same year. In 2013, the current research information system – Ciência-IUL – became interoperable with the Repository bringing new challenges to SID, and allowing work collaboratively with other services to collect information, improve processes, and reduce duplication of efforts. SID seeks to support researchers throughout the research life cycle aiming to raise awareness of the academic community for Open Science best practices.info:eu-repo/semantics/publishedVersio
“Renewable Energy Systems”: Role and Use of Parliamentary Technology Assessment. Liège, Belgium, June 25 - 28, 2012
„Renewable Energy Systems“: Role and Use of Parliamentary Technology Assessment: Liége, Belgium, June 25-28, 2012
Arabidopsis Tetraspanins Are Confined to Discrete Expression Domains and Cell Types in Reproductive Tissues and Form Homo- and Heterodimers When Expressed in Yeast
Tetraspanins are evolutionary conserved transmembrane proteins present in all multicellular organisms. In animals, they are known to act as central organizers of membrane complexes and thought to facilitate diverse biological processes, such as cell proliferation, movement, adhesion, and fusion. The genome of Arabidopsis (Arabidopsis thaliana) encodes 17 members of the tetraspanin family; however, little is known about their functions in plant development. Here, we analyzed their phylogeny, protein topology, and domain structure and surveyed their expression and localization patterns in reproductive tissues. We show that, despite their low sequence identity with metazoan tetraspanins, plant tetraspanins display the typical structural topology and most signature features of tetraspanins in other multicellular organisms. Arabidopsis tetraspanins are expressed in diverse tissue domains or cell types in reproductive tissues, and some accumulate at the highest levels in response to pollination in the transmitting tract and stigma, male and female gametophytes and gametes. Arabidopsis tetraspanins are preferentially targeted to the plasma membrane, and they variously associate with specialized membrane domains, in a polarized fashion, to intercellular contacts or plasmodesmata. A membrane-based yeast (Saccharomyces cerevisiae) two-hybrid system established that tetraspanins can physically interact, forming homo- and heterodimer complexes. These results, together with a likely genetic redundancy, suggest that, similar to their metazoan counterparts, plant tetraspanins might be involved in facilitating intercellular communication, whose functions might be determined by the composition of tetraspanin complexes and their binding partners at the cell surface of specific cell types.Marie Curie International Reintegration grant: (no. IRG–256602), U.S. Department of Agriculture-Agricultural Research Service Current Research Information System grant: (5335–21000–030–00D), Fundação
Ciência e Tecnologia Postdoctoral Fellowship: (SFRH/BPD/43584/2008), China Scholarship Council fellowship, UC-Berkeley College of Natural Resources SPUR
Combination of trans-resveratrol and E-viniferin induces a hepatoprotective effect in rats with severe acute liver failure via reduction of oxidative stress and MMP-9 expression
Stilbenes are a major grapevine class of phenolic compounds, known for their biological
activities, including anti-inflammatory and antioxidant, but never studied in combination. We
aimed to evaluate the effect of trans-resveratrol + "-viniferin as an antioxidant mixture and its role
in inflammatory development an in vivo model of severe acute liver failure induced with TAA.
Trans-resveratrol + trans-"-viniferin (5 mg/kg each) was administered to Wistar rats. Resveratrol + "-
viniferin significantly decreased TBARS and SOD activity and restored CAT and GST activities in
the treated group. This stilbene combination reduced the expression of TNF , iNOS, and COX-2,
and inhibited MMP-9. The combination of resveratrol + "-viniferin had a hepatoprotective effect,
reducing DNA damage, exhibiting a protective role on the antioxidant pathway by altering SOD,
CAT, and GST activities; by downregulating TNF , COX-2, and iNOS; and upregulating IL-10. Our
results suggested that adding viniferin to resveratrol may be more effective in hepatoprotection than
resveratrol alone, opening a new perspective on using this stilbene combination in functional dietsinfo:eu-repo/semantics/publishedVersio
As Bibliotecas de Ensino Superior e a gestão de ciência
As Bibliotecas de Ensino Superior (BES) com sistemas CRIS e repositórios institucionais a seu cargo têm vindo a adaptar-se no sentido de responder às necessidades dos seus utilizadores. Passaram a incluir funções de gestão de ciência com benefícios para a comunidade científica e para a instituição. Com a proliferação de plataformas digitais dedicadas à disseminação e comunicação de ciência surgiu a necessidade de apoiar os docentes e investigadores na atualização da sua produção científica e proceder à validação de metadados, ajudando a manter a qualidade e veracidade da informação e contribuir para a simplificação e transparência dos processos de avaliação da instituição. Pretende-se, com este trabalho, descrever a atividade de uma Biblioteca de Ensino Superior com funções de gestão de ciência, enfatizando a interação CRIS-repositório institucional, o processo de validação de metadados e a atualização de perfil de investigador e respetivos currículos dos docentes e investigadores.info:eu-repo/semantics/publishedVersio
As Bibliotecas de Ensino Superior e a Gestão de Ciência
As Bibliotecas de Ensino Superior (BES) com sistemas CRIS e repositórios institucionais a seu cargo têm vindo a adaptar-se no sentido de responder às necessidades dos seus utilizadores. Passaram a incluir funções de gestão de ciência com benefícios para a comunidade científica e para a instituição. Com a proliferação de plataformas digitais dedicadas à disseminação e comunicação de ciência surgiu a necessidade de apoiar os docentes e investigadores na atualização da sua produção científica e proceder à validação de metadados, ajudando a manter a qualidade e veracidade da informação e contribuir para a simplificação e transparência dos processos de avaliação da instituição. Pretende-se, com este trabalho, descrever a atividade de uma Biblioteca de Ensino Superior com funções de gestão de ciência, enfatizando a interação CRIS-repositório institucional, o processo de validação de metadados e a atualização de perfil de investigador e respetivos currículos dos docentes e investigadores.info:eu-repo/semantics/publishedVersio
FACS-based purification of Arabidopsis microspores, sperm cells and vegetative nuclei
Background:
The male germline in flowering plants differentiates by asymmetric division of haploid uninucleated
microspores, giving rise to a vegetative cell enclosing a smaller generative cell, which eventually undergoes a
second mitosis to originate two sperm cells. The vegetative cell and the sperm cells activate distinct genetic and epigenetic mechanisms to control pollen tube growth and germ cell specification, respectively. Therefore, a comprehensive characterization of these processes relies on efficient methods to isolate each of the different cell types throughout male gametogenesis.
Results:
We developed stable transgenic Arabidopsis lines and reliable purification tools based on
Fluorescence-Activated Cell Sorting (FACS) in order to isolate highly pure and viable fractions of each cell/nuclei type before and after pollen mitosis. In the case of mature pollen, this was accomplished by expressing GFP and RFP in the sperm and vegetative nuclei, respectively, resulting in 99% pure sorted populations. Microspores were also purified by FACS taking advantage of their characteristic small size and autofluorescent properties, and were confirmed to be 98% pure.
Conclusions:
We provide simple and efficient FACS-based purification protocols for Arabidopsis microspores, vegetative nuclei and sperm cells. This paves the way for subsequent molecular analysis such as transcriptomics, DNA methylation analysis and chromatin immunoprecipitation, in the developmental context of microgametogenesis in Arabidopsis.NSERC graduate student fellowship; Fred C. Gloeckner Foundation grant
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