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1.
J Eur CME ; 8(1): 1685771, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31807368

RESUMO

The European Federation of Pharmaceutical Industries and Associations (EFPIA) representing the pharmaceutical industry operating in Europe, introduced three codes of conduct between 2007 and 2013, which had a common goal of self-regulating interactions with healthcare professionals and patient organisations. This former set of rules was appreciated as a first self-regulatory step, although self-regulation itself is still considered by many stakeholders as insufficient to provide thorough transparency. EFPIA agreed to replace the separate codes with a new, consolidated EFPIA Code of Practice. The consolidated Code was broadened to include a new section on medical education that outlines the scope of member companies' engagement in "medical education activities?. This new section is controversial as it explicitly confirms that EFPIA members can be involved in medical education. In our view "independent Medical Education" per se prevents industry from "organising" events, i.e. industry must not influence content, presentation, choice of lecturers or publication of results. What is more, only events respecting this key principle (amongst others) can be recognised for purposes of continuing medical education/continuing professional development (CME/CPD). A substantial portion of the medical education is currently funded by the pharmaceutical and medical device industries. This practice carries a significant risk to public and personal health, especially if it is not adequately safeguarded by a high standard of accreditation. We are most concerned by the fact that EFPIA, representing the pharmaceutical industry, is trying to broaden the approach to medical education, to include activities that are not independently evaluated as free from undue influence and conflicts of interest. We believe that in order to preserve scientific integrity and independence, pharmaceutical companies must not be granted the right to influence the content of medical education.

2.
Transgenic Res ; 20(1): 61-72, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20397044

RESUMO

The most devastating disease currently threatening to destroy the banana industry worldwide is undoubtedly Sigatoka Leaf spot disease caused by Mycosphaerella fijiensis. In this study, we developed a transformation system for banana and expressed the endochitinase gene ThEn-42 from Trichoderma harzianum together with the grape stilbene synthase (StSy) gene in transgenic banana plants under the control of the 35S promoter and the inducible PR-10 promoter, respectively. The superoxide dismutase gene Cu,Zn-SOD from tomato, under control of the ubiquitin promoter, was added to this cassette to improve scavenging of free radicals generated during fungal attack. A 4-year field trial demonstrated several transgenic banana lines with improved tolerance to Sigatoka. As the genes conferring Sigatoka tolerance may have a wide range of anti-fungal activities we also inoculated the regenerated banana plants with Botrytis cinerea. The best transgenic lines exhibiting Sigatoka tolerance were also found to have tolerance to B. cinerea in laboratory assays.


Assuntos
Ascomicetos/patogenicidade , Botrytis/patogenicidade , Musa/enzimologia , Musa/genética , Doenças das Plantas/microbiologia , Plantas Geneticamente Modificadas/genética , Trichoderma/enzimologia , Aciltransferases/genética , Aciltransferases/metabolismo , Ascomicetos/classificação , Botrytis/classificação , Quitinases/genética , Quitinases/metabolismo , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/enzimologia , Solanum lycopersicum/genética , Musa/microbiologia , Plantas Geneticamente Modificadas/microbiologia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Transformação Genética , Trichoderma/genética , Vitis/enzimologia , Vitis/genética
3.
Plant Cell Physiol ; 51(7): 1151-62, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20530511

RESUMO

Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is overexpressed in plants under abiotic and biotic stress conditions that mediate oxidative stress. To study its biological role and its ability to confer stress resistance in plants, we tried to obtain transgenic plants overexpressing citrus (Citrus sinensis) PHGPx (cit-PHGPx). All attempts to obtain regenerated plants expressing this enzyme constitutively failed. However, when the enzyme's catalytic activity was abolished by active site-directed mutagenesis, transgenic plants constitutively expressing inactive cit-PHGPx were successfully regenerated. Constitutive expression of enzymatically active cit-PHGPx could only be obtained when transformation was based on non-regenerative processes. These results indicate that overexpression of the antioxidant enzyme PHGPx interferes with shoot organogenesis and suggests the involvement of reactive oxygen species (ROS) in this process. Using transgenic tobacco (Nicotiana tabacum) leaves obtained from plants transformed with a beta-estradiol-inducible promoter, time-dependent induction of cit-PHGPx expression was employed. A pronounced inhibitory effect of cit-PHGPx on shoot formation was found to be limited to the early stage of the regeneration process. Monitoring the ROS level during regeneration revealed that upon cit-PHGPx induction, the lowest level of ROS correlated with the maximal level of shoot inhibition. Our results clearly demonstrate the essential role of ROS in the early stages of in vitro shoot organogenesis and the possible involvement of PHGPx in maintaining ROS homeostasis at this point.


Assuntos
Glutationa Peroxidase/metabolismo , Nicotiana/crescimento & desenvolvimento , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Citrus/enzimologia , Regulação da Expressão Gênica de Plantas , Homeostase , Mutagênese Sítio-Dirigida , Oxirredução , Brotos de Planta/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Regeneração , Estresse Fisiológico , Nicotiana/metabolismo , Transformação Genética
4.
Plant Cell Rep ; 28(7): 1033-42, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19479258

RESUMO

In Vitis vinifera L. cv. Thompson Seedless, fertilization occurs but seeds abort, a type of stenospermocarpy. To clone transcripts with differential expression during flower development, suppressive subtractive hybridization was carried out using two isogenic clones 'Thompson seedless' and 'Thompson seeded', at three stages of inflorescence development (from bud break to ~20 days prior to anthesis). Differential screening and sequencing of a forward and reverse subtractive cDNA library yielded several singleton ESTs. One differentially expressed clone in 'Thompson' seeded versus seedless isogenic clones was the ubiquitin extension protein S27a. In situ hybridization demonstrated its significantly higher expression in the carpel and ovaries of 'Thompson' seedless versus seeded isogenic clones during flower development. Overexpression of this gene resulted in abnormal plant regeneration and inhibited shoot development compared to controls; its silencing in embryogenic callus induced cell necrosis and callus death, evidencing tight regulation of this gene in developing organs of grape. S27a overexpression in carpels and integuments of the seedless flower may interfere with normal development of these organs, leading to embryo abortion and seedlessness.


Assuntos
Flores/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Ribossômicas/metabolismo , Ubiquitina/metabolismo , Vitis/crescimento & desenvolvimento , Sequência de Aminoácidos , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Inativação Gênica , Genes de Plantas , Dados de Sequência Molecular , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , RNA de Plantas/genética , Proteínas Ribossômicas/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Ubiquitina/genética , Vitis/genética , Vitis/metabolismo
5.
Plant Sci ; 176(4): 566-74, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26493147

RESUMO

Ubiquitin is a highly conserved 76-amino-acid protein found in all eukaryotic cells. Ubiquitin's expression is encoded and expressed as multimeric head-to-tail repeats (polyubiquitins) that are post-translationally cleaved into monomers, or fused with ribosomal proteins S27a and L40. S27a is highly expressed in meristematic tissues, pollen and ovules and its ubiquitin moiety is thought to act as a chaperone in ribosome biogenesis prior to cleavage. This study suggests that the ribosomal protein S27a plays a critical role in the allocation of meristematic cells that differentiate into lateral structures such as leaves and flowers. S27a was also found to regulate floral meristem development, possibly through the control of cell proliferation as well as cell identity. Overexpression of S27a was correlated with increased proliferation of undifferentiated cells and arrest of morphologically "normal" shoot and leaf development. The ubiquitin moiety did not affect the localization of S27a, but it did affect its protein level: expression of S27a without the ubiquitin moiety caused a severe reduction in S27a protein level.

6.
Transgenic Res ; 16(4): 515-25, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17103240

RESUMO

Vitis vinifera L. cv. 'Thompson Seedless' presents a type of stenospermocarpy in grape where fertilization occurs but seeds abort and fail to develop. To unravel the molecular basis for stenospermocarpy in grapes, subtractive hybridization was carried out in order to isolate differentially regulated genes that participate in the seedlessness machinery. Two 'Thompson' lines, a seeded and a seedless, were screened during different flower developmental stages. One of the genes, that was differentially expressed between the seeded and seedless lines, was the chloroplast chaperonin 21 (ch-Cpn21). ch-Cpn21 is a 21-kDa co-chaperonin polypeptide formed by two GroES-like domains fused together in tandem. Silencing of ch-Cpn21 in Nicotiana benthamiana plants resulted in leaf stunting, chlorosis, as well as ovary necrogenesis leading to seed abortion. Moreover, organ-specific silencing of ch-Cpn21 only in Lycopersicum esculentum fruits resulted in the development of seedless tomatoes. These results suggest that ch-Cpn21 may play a role in seed abortion in stenospermocarpic grapes.


Assuntos
Chaperoninas/genética , Regulação para Baixo/genética , Flores/química , Inativação Gênica/fisiologia , Nicotiana/citologia , Sementes/química , Solanum lycopersicum/crescimento & desenvolvimento , Vitis/química , Chaperoninas/antagonistas & inibidores , Chaperoninas/metabolismo , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Sementes/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Vitis/genética , Vitis/crescimento & desenvolvimento
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