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1.
Eur J Neurol ; 26(1): 41-50, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30035845

RESUMO

BACKGROUND AND PURPOSE: Patient and public involvement in clinical practice guideline development is recommended to increase guideline trustworthiness and relevance. The aim was to engage multiple sclerosis (MS) patients and caregivers in the definition of the key questions to be answered in the European Academy of Neurology guideline on palliative care of people with severe MS. METHODS: A mixed methods approach was used: an international online survey launched by the national MS societies of eight countries, after pilot testing/debriefing on 20 MS patients and 18 caregivers, focus group meetings of Italian and German MS patients and caregivers. RESULTS: Of 1199 participants, 951 (79%) completed the whole online survey and 934 from seven countries were analysed: 751 (80%) were MS patients (74% women, mean age 46.1) and 183 (20%) were caregivers (36% spouses/partners, 72% women, mean age 47.4). Participants agreed/strongly agreed on inclusion of the nine pre-specified topics (from 89% for 'advance care planning' to 98% for 'multidisciplinary rehabilitation'), and <5% replied 'I prefer not to answer' to any topic. There were 569 free comments: 182 (32%) on the pre-specified topics, 227 (40%) on additional topics (16 guideline-pertinent) and 160 (28%) on outcomes. Five focus group meetings (three of MS patients, two of caregivers, and overall 35 participants) corroborated the survey findings. In addition, they allowed an explanation of the guideline production process and the exploration of patient-important outcomes and of taxing issues. CONCLUSIONS: Multiple sclerosis patient and caregiver involvement was resource and time intensive, but rewarding. It was the key for the formulation of the 10 guideline questions and for the identification of patient-important outcomes.


Assuntos
Cuidadores , Guias como Assunto , Esclerose Múltipla/terapia , Cuidados Paliativos/normas , Pacientes , Adulto , Planejamento Antecipado de Cuidados , Idoso , Participação da Comunidade , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/reabilitação , Equipe de Assistência ao Paciente , Inquéritos e Questionários , Resultado do Tratamento
2.
Eur J Neurol ; 24(7): 995-998, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28544000

RESUMO

BACKGROUND AND PURPOSE: A Consensus document on palliative care and neurology has made recommendations on the care of people with chronic and progressive neurological disease. This study aimed to investigate whether these recommendations are understood by, acceptable to and used in practice by neurologists in Belgium. METHODS: An online survey was undertaken of 100 neurologists in Belgium, asking for their opinion on all of the recommendations in the Consensus document. RESULTS: Sixty-four of the neurologists replied. Overall, they expressed support for the recommendations, in particular open communication with patients, open assessment of patient and family needs, and discussion of dying. There was less understanding of the role of palliative care in the implementation of palliative care early in disease progression and the role of palliative care multidisciplinary teams. CONCLUSIONS: The survey shows that many of the recommendations in the European Academy of Neurology/European Association for Palliative Care Taskforce on Neurology Consensus document are understood by neurologists, and several are now seen as part of normal clinical practice. However, there is still a need to develop a more collaborative approach between neurology and palliative care services, for the benefit of patients and families.


Assuntos
Doenças do Sistema Nervoso/terapia , Neurologistas , Cuidados Paliativos/normas , Bélgica , Doença Crônica , Consenso , Morte , Progressão da Doença , Europa (Continente) , Família , Pesquisas sobre Atenção à Saúde , Equipe de Assistência ao Paciente , Inquéritos e Questionários
3.
BMJ Support Palliat Care ; 7(2): 164-172, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26182947

RESUMO

BACKGROUND: This study analysed the impact on palliative care outcomes of a new specialist palliative care service for patients severely affected by amyotrophic lateral sclerosis (ALS/MND), multiple sclerosis, Parkinson's disease and related disorders (multiple system atrophy progressive supranuclear palsy, MSA-PSP). METHODS: The design followed the Medical Research Council Framework for the evaluation of complex interventions. A phase II randomised controlled trial (RCT) was undertaken comparing an immediate referral to the service (FT, fast track) to a 16-week wait (standard track (ST), standard best practice) using a parallel arm design. The main outcome measures were Quality of Life (measured with Schedule for the Evaluation of Individual Quality of Life Direct Weight, SEIQoL-DW) and burden of the carers (Caregivers Burden Inventory, CBI), with secondary outcomes of symptoms, psychosocial and spiritual issues. RESULTS: 50 patients severely affected by neurodegenerative conditions and their informal family carers were randomised: 25 FT, 25 ST. At baseline (T0), there were no differences between groups. 4 patients died during the follow-up (2 FT, 2 ST) and 2 FT patients dropped out before the end of the study. After 16 weeks (T1), FT participants scored significant improvement in the SEIQoL-DW index, pain dyspnoea sleep disturbance and bowel symptoms. CONCLUSIONS: This exploratory RCT provides evidence that no harm was experienced by SPCS for patients severely affected by neurodegenerative disorders. There was an improvement in quality of life and physical symptoms for neurological patients in palliative care. Caregiver burden was not affected by the service.


Assuntos
Doenças Neurodegenerativas/psicologia , Qualidade de Vida , Adulto , Idoso , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Projetos Piloto , Resultado do Tratamento
4.
Eur J Neurol ; 23(1): 30-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26423203

RESUMO

BACKGROUND AND PURPOSE: The European Association of Palliative Care Taskforce, in collaboration with the Scientific Panel on Palliative Care in Neurology of the European Federation of Neurological Societies (now the European Academy of Neurology), aimed to undertake a review of the literature to establish an evidence-based consensus for palliative and end of life care for patients with progressive neurological disease, and their families. METHODS: A search of the literature yielded 942 articles on this area. These were reviewed by two investigators to determine the main areas and the subsections. A draft list of papers supporting the evidence for each area was circulated to the other authors in an iterative process leading to the agreed recommendations. RESULTS: Overall there is limited evidence to support the recommendations but there is increasing evidence that palliative care and a multidisciplinary approach to care do lead to improved symptoms (Level B) and quality of life of patients and their families (Level C). The main areas in which consensus was found and recommendations could be made are in the early integration of palliative care (Level C), involvement of the wider multidisciplinary team (Level B), communication with patients and families including advance care planning (Level C), symptom management (Level B), end of life care (Level C), carer support and training (Level C), and education for all professionals involved in the care of these patients and families (Good Practice Point). CONCLUSIONS: The care of patients with progressive neurological disease and their families continues to improve and develop. There is a pressing need for increased collaboration between neurology and palliative care.


Assuntos
Consenso , Esclerose Múltipla/terapia , Doenças Neurodegenerativas/terapia , Neurologia/normas , Cuidados Paliativos/normas , Sociedades Médicas/normas , Assistência Terminal/normas , Humanos , Doenças do Sistema Nervoso
5.
Nanotechnology ; 25(2): 025701, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24334512

RESUMO

We have carried out nanoindentation studies of gold in which the indenter is atomically characterized by field-ion microscopy and the scale of deformation is sufficiently small to be directly compared with atomistic simulations. We find that many features of the experiment are correctly reproduced by molecular dynamics simulations, in some cases only when an atomically rough indenter rather than a smooth repulsive-potential indenter is used. Heterogeneous nucleation of dislocations is found to take place at surface defect sites. Using input from atomistic simulations, a model of indentation based on stochastic transitions between continuum elastic-plastic states is developed, which accurately predicts the size distributions of plastic 'pop-in' events and their dependence on tip geometry.

6.
Prikl Biokhim Mikrobiol ; 48(3): 289-93, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22834299

RESUMO

The E. coli propionyl-CoA synthetase (PCS) was cloned, expressed, purified, and analyzed. Kinetic analyses suggested that the enzyme preferred propionate as substrate but would also use acetate. The purified, stored protein had relatively low activity but was activated up to about 10-fold by incubation with dithiothreitol (DTT). The enzyme activation by DTT was reversed by diamide. This suggests that the protein contains a regulatory disulfide bond and that the reduction to two sulfhydryl groups activates PCS while the oxidation to a disulfide leads to its inactivation. This idea was tested by sequential mutagenesis of the 9 Cys in the protein to Ala. It was revealed that the C128A and C315A mutants had wildtype enzyme activity but were no longer activated by DTT or inhibited by diamide. The data obtained indicate that two Cys residues could be involved in redox-regulated system through formation of an intramolecular disulfide bridge in PCS.


Assuntos
Coenzima A Ligases/química , Cisteína/química , Dissulfetos/química , Proteínas de Escherichia coli/química , Escherichia coli/enzimologia , Clonagem Molecular , Coenzima A Ligases/genética , Coenzima A Ligases/isolamento & purificação , Cisteína/genética , Ditiotreitol/química , Ativação Enzimática , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/isolamento & purificação , Oxirredução , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
7.
Nanotechnology ; 19(47): 475709, 2008 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-21836290

RESUMO

We investigate the mechanical response of 50-600 nm epitaxial Ge films on a Si substrate using nanoindentation with a nominally spherical (R≈4.3 µm) diamond tip. The inelastic deformation mechanism is found to depend critically on the film thickness. Sub-100 nm Ge films deform by pressure-induced phase transformation, whereas thicker films deform only by shear-induced dislocation slip and twinning. Nanoindentation fracture response is similarly dependent on film thickness. Elastic stress modelling shows that differing stress modes vary in their spatial distribution, and consequently the film thickness governs the stress state in the film, in conjunction with the radius of the nanoindenter tip. This opens the prospect of tailoring the contact response of Ge and related materials in thin film form by varying film thickness and indenter radius.

8.
Plant Physiol Biochem ; 44(11-12): 885-92, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17123825

RESUMO

One of the key steps in developing transgenic plants for the phytoremediation of metal containing soils is to develop plants that accumulate metals in the aerial tissues. With the goal of changing the distribution of phytochelatin (PC)-dependent cadmium accumulation from roots to the leaves, the phytochelatin synthase (PCS) deficient cad1-3 mutant and wild type (Col-0) Arabidopsis plants were transformed with an Arabidopsis phytochelatin synthase (AtPCS1) under the control of a leaf-specific promoter. Three independent transformant lines from each genetic background were chosen for further analysis and designated cad-PCS and WT-PCS. PCS activity in the cadPCS lines was restored in the leaves, but not in the roots. Additionally, when whole plants were treated with cadmium, PCs were found only in the leaves of cad-PCS plants. Although the inserted AtPCS1 gene was leaf-specific, cad-PCS lines showed an overall decrease in cadmium toxicity evidenced by a partial amelioration of the "brown-root" phenotype and root growth was restored to wild type levels when treated with cadmium and arsenate. WT-PCS lines showed an increase in leaf PCS activity but had only wild type PC levels. In addition, cadmium uptake studies indicated that there was no difference in cadmium accumulation among all types tested. So, while we were able to protect the plants against cadmium by expressing PC synthase only in the leaves, we were not able to limit cadmium accumulation to aerial tissues.


Assuntos
Proteínas de Arabidopsis/biossíntese , Arabidopsis/enzimologia , Cádmio/farmacologia , Folhas de Planta/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/genética , Cádmio/metabolismo , Resistência a Medicamentos/efeitos dos fármacos , Resistência a Medicamentos/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Folhas de Planta/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética
9.
Palliat Med ; 17(4): 322-6, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12822848

RESUMO

Following an audit to determine the standards of the assessment and management of dysphagia within the Wisdom Hospice, a standardized, multidisciplinary dysphagia policy was established, incorporating a dysphagia trained nurse (DTN) scheme. The standards of care of dysphagic patients were audited after its introduction and the results indicate that the resourcing and quality of care difficulties identified have been improved by the implementation of the policy. The service development implications for the management of dysphagia in palliative care settings are discussed.


Assuntos
Transtornos de Deglutição/terapia , Hospitais para Doentes Terminais/normas , Cuidados Paliativos/normas , Formulação de Políticas , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/enfermagem , Humanos , Auditoria Médica , Doença dos Neurônios Motores/complicações , Cuidados Paliativos/métodos , Reino Unido
11.
Plant Physiol ; 127(2): 615-23, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11598235

RESUMO

In contrast to peas (Pisum sativum), where mitochondrial lipoamide dehydrogenase is encoded by a single gene and shared between the alpha-ketoacid dehydrogenase complexes and the Gly decarboxylase complex, Arabidopsis has two genes encoding for two mitochondrial lipoamide dehydrogenases. Northern-blot analysis revealed different levels of RNA expression for the two genes in different organs; mtLPD1 had higher RNA levels in green leaves compared with the much lower level in roots. The mRNA for mtLPD2 shows the inverse pattern. The other organs examined showed nearly equal RNA expressions for both genes. Analysis of etiolated seedlings transferred to light showed a strong induction of RNA expression for mtLPD1 but only a moderate induction of mtLPD2. Based on the organ and light-dependent expression patterns, we hypothesize that mtLPD1 encodes the protein most often associated with the Gly decarboxylase complex, and mtLPD2 encodes the protein incorporated into alpha-ketoacid dehydrogenase complexes. Due to the high level of sequence conservation between the two mtLPDs, we assume that the proteins, once in the mitochondrial matrix, are interchangeable among the different multienzyme complexes. If present at high levels, one mtLPD might substitute for the other. Supporting this hypothesis are results obtained with a T-DNA knockout mutant, mtlpd2, which shows no apparent phenotypic change under laboratory growth conditions. This indicates that mtLPD1 can substitute for mtLPD2 and associate with all these multienzyme complexes.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/enzimologia , Di-Hidrolipoamida Desidrogenase/genética , Mitocôndrias/genética , Complexos Multienzimáticos/genética , Aminoácido Oxirredutases/genética , Aminoácido Oxirredutases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , DNA Complementar , DNA Mitocondrial , DNA de Plantas , Di-Hidrolipoamida Desidrogenase/metabolismo , Regulação da Expressão Gênica de Plantas , Glicina Desidrogenase (Descarboxilante) , Mitocôndrias/enzimologia , Complexos Multienzimáticos/metabolismo , Pisum sativum/enzimologia , Pisum sativum/genética , Folhas de Planta/enzimologia , Folhas de Planta/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Plantas Geneticamente Modificadas , Piruvato Desidrogenase (Lipoamida)/genética , Piruvato Desidrogenase (Lipoamida)/metabolismo , Transdução de Sinais
12.
Electrophoresis ; 22(9): 1724-38, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11425228

RESUMO

As a first step in establishing a proteome database for maize, we have embarked on the identification of the leaf proteins resolved on two-dimensional (2-D) gels. We detected nearly 900 spots on the gels with a pH 4-7 gradient and over 200 spots on the gels with a pH 6-11 gradient when the proteins were visualized with colloidal Coomassie blue. Peptide mass fingerprints for 300 protein spots were obtained with matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometer and 149 protein spots were identified using the protein databases. We also searched the pdbEST databases to identify the leaf proteins and verified 66% of the protein spots that had been identified using the protein databases. Sixty-seven additional protein spots were identified from expressed sequence tags (ESTs). Many abundant leaf proteins are present in multiple spots. Functions of over 50% of the abundant leaf proteins are either unknown or hypothetical. Our results show that EST databases in conjunction with peptide mass fingerprints can be used for identifying proteins from organisms with incomplete genome sequence information.


Assuntos
Proteoma/análise , Zea mays/metabolismo , Eletroforese em Gel Bidimensional/métodos , Genoma de Planta , Mapeamento de Peptídeos/métodos , Proteínas de Plantas/análise , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Zea mays/genética
13.
Plant Physiol ; 126(2): 564-74, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11402187

RESUMO

A functional analysis of the role of glutathione in protecting plants from environmental stress was undertaken by studying Arabidopsis that had been genetically modified to have altered glutathione levels. The steady-state glutathione concentration in Arabidopsis plants was modified by expressing the cDNA for gamma-glutamyl-cysteine synthetase (GSH1) in both the sense and antisense orientation. The resulting plants had glutathione levels that ranged between 3% and 200% of the level in wild-type plants. Arabidopsis plants with low glutathione levels were hypersensitive to Cd due to the limited capacity of these plants to make phytochelatins. Plants with the lowest levels of reduced glutathione (10% of wild type) were sensitive to as little as 5 microM Cd, whereas those with 50% wild-type levels required higher Cd concentrations to inhibit growth. Elevating glutathione levels did not increase metal resistance. It is interesting that the plants with low glutathione levels were also less able to accumulate anthocyanins supporting a role for glutathione S-transferases for anthocyanin formation or for the vacuolar localization and therefore accumulation of these compounds. Plants with less than 5% of wild-type glutathione levels were smaller and more sensitive to environmental stress but otherwise grew normally.


Assuntos
Arabidopsis/fisiologia , Glutationa/fisiologia , Antocianinas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Cromatografia Líquida de Alta Pressão , Glutamato-Cisteína Ligase/genética , Glutationa/metabolismo , Metais Pesados/toxicidade , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
FEBS Lett ; 484(1): 12-6, 2000 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-11056213

RESUMO

Lipoamide dehydrogenase is a subunit of the alpha-ketoacid dehydrogenases and the glycine decarboxylase complex in mitochondria, and the pyruvate dehydrogenase complex in plastids. We report here the unexpected finding of two plastidic isoforms of lipoamide dehydrogenase from Arabidopsis thaliana that are different from the mitochondrial form of the enzyme. The cDNA clones were confirmed by sequence alignment analysis and their location verified by chloroplast import assay. They are single copy genes that appear to be expressed in parallel in different tissues with highest level in developing siliques. Phylogenetic analysis gives further exemplary evidence for the plastidic evolution derived from cyanobacteria.


Assuntos
Arabidopsis/enzimologia , Di-Hidrolipoamida Desidrogenase/metabolismo , Plastídeos/enzimologia , Sequência de Aminoácidos , Arabidopsis/citologia , Arabidopsis/genética , Arabidopsis/metabolismo , Núcleo Celular/genética , Cloroplastos/enzimologia , Cloroplastos/genética , Cloroplastos/metabolismo , Clonagem Molecular , Cianobactérias/enzimologia , Di-Hidrolipoamida Desidrogenase/química , Di-Hidrolipoamida Desidrogenase/genética , Genes de Plantas/genética , Mitocôndrias/enzimologia , Dados de Sequência Molecular , Pisum sativum/citologia , Pisum sativum/metabolismo , Filogenia , Plastídeos/genética , Plastídeos/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/genética , RNA de Plantas/análise , RNA de Plantas/genética , Alinhamento de Sequência
15.
Plant Physiol ; 123(2): 497-508, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10859180

RESUMO

Acetyl-coenzyme A (acetyl-CoA) formed within the plastid is the precursor for the biosynthesis of fatty acids and, through them, a range of important biomolecules. The source of acetyl-CoA in the plastid is not known, but two enzymes are thought to be involved: acetyl-CoA synthetase and plastidic pyruvate dehydrogenase. To determine the importance of these two enzymes in synthesizing acetyl-CoA during lipid accumulation in developing Arabidopsis seeds, we isolated cDNA clones for acetyl-CoA synthetase and for the ptE1alpha- and ptE1beta-subunits of plastidic pyruvate dehydrogenase. To our knowledge, this is the first reported acetyl-CoA synthetase sequence from a plant source. The Arabidopsis acetyl-CoA synthetase preprotein has a calculated mass of 76,678 D, an apparent plastid targeting sequence, and the mature protein is a monomer of 70 to 72 kD. During silique development, the spatial and temporal patterns of the ptE1beta mRNA level are very similar to those of the mRNAs for the plastidic heteromeric acetyl-CoA carboxylase subunits. The pattern of ptE1beta mRNA accumulation strongly correlates with the formation of lipid within the developing embryo. In contrast, the level of mRNA for acetyl-CoA synthetase does not correlate in time and space with lipid accumulation. The highest level of accumulation of the mRNA for acetyl-CoA synthetase during silique development is within the funiculus. These mRNA data suggest a predominant role for plastidic pyruvate dehydrogenase in acetyl-CoA formation during lipid synthesis in seeds.


Assuntos
Acetato-CoA Ligase/metabolismo , Arabidopsis/enzimologia , Ácidos Graxos/biossíntese , Complexo Piruvato Desidrogenase/metabolismo , Sementes/enzimologia , Acetato-CoA Ligase/química , Acetato-CoA Ligase/genética , Sequência de Aminoácidos , Arabidopsis/embriologia , Clonagem Molecular , Hibridização In Situ , Dados de Sequência Molecular , Plastídeos/enzimologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sementes/crescimento & desenvolvimento , Homologia de Sequência de Aminoácidos
16.
Biochem Soc Trans ; 28(6): 591-3, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11171136

RESUMO

We have characterized the expression of potential acetyl-CoA-generating genes (acetyl-CoA synthetase, pyruvate decarboxylase, acetaldehyde dehydrogenase, plastidic pyruvate dehydrogenase complex and ATP-citrate lyase), and compared these with the expression of acetyl-CoA-metabolizing genes (heteromeric and homomeric acetyl-CoA carboxylase). These comparisons have led to the development of testable hypotheses as to how distinct pools of acetyl-CoA are generated and metabolized. These hypotheses are being tested by combined biochemical, genetic and molecular biological experiments, which is providing insights into how acetyl-CoA metabolism is regulated.


Assuntos
Acetilcoenzima A/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , ATP Citrato (pro-S)-Liase/genética , Acetato-CoA Ligase/genética , Aldeído Oxirredutases/genética , Biologia Molecular/métodos , Plastídeos/enzimologia , Piruvato Descarboxilase/genética , Complexo Piruvato Desidrogenase/genética
17.
Plant Mol Biol ; 40(4): 711-7, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10480394

RESUMO

A streamlined mini binary vector was constructed that is less than 1/2 the size of the pBIN19 backbone (3.5 kb). This was accomplished by eliminating over 5 kb of non-T-DNA sequences from the pBIN19 vector. The vector still retains all the essential elements required for a binary vector. These include a RK2 replication origin, the nptIII gene conferring kanamycin resistance in bacteria, both the right and left T-DNA borders, and a multiple cloning site (MCS) in between the T-DNA borders to facilitate cloning. Due to the reduced size, more unique restriction sites are available in the MCS, thus allowing more versatile cloning. Since the traF region was not included, it is not possible to mobilize this binary vector into Agrobacterium by triparental mating. This problem can be easily resolved by direct transformation. The mini binary vector has been demonstrated to successfully transform Arabidopsis plants. Based on this mini binary vector, a series of binary vectors were constructed for plant transformation.


Assuntos
Vetores Genéticos/genética , Plantas/genética , Transformação Genética , Agrobacterium tumefaciens/genética , Arabidopsis/genética , Southern Blotting , Clonagem Molecular , DNA Bacteriano/genética , DNA de Plantas/genética , Vetores Genéticos/química , Dados de Sequência Molecular , Análise de Sequência de DNA
18.
Plant Cell ; 10(9): 1539-50, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9724699

RESUMO

Glutathione plays a pivotal role in protecting plants from environmental stresses, oxidative stress, xenobiotics, and some heavy metals. Arabidopsis plants treated with cadmium or copper responded by increasing transcription of the genes for glutathione synthesis, gamma-glutamylcysteine synthetase and glutathione synthetase, as well as glutathione reductase. The response was specific for those metals whose toxicity is thought to be mitigated through phytochelatins, and other toxic and nontoxic metals did not alter mRNA levels. Feeding experiments suggested that neither oxidative stress, as results from exposure to H2O2, nor oxidized or reduced glutathione levels were responsible for activating transcription of these genes. Jasmonic acid also activated the same suite of genes, which suggests that it might be involved in the signal transduction pathway for copper and cadmium. Jasmonic acid treatment increased mRNA levels and the capacity for glutathione synthesis but did not alter the glutathione content in unstressed plants, which supports the idea that the glutathione concentration is controlled at multiple levels.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Genes de Plantas , Glutationa/metabolismo , Arabidopsis/efeitos dos fármacos , Ciclopentanos/farmacologia , Expressão Gênica/efeitos dos fármacos , Genes de Plantas/efeitos dos fármacos , Glutationa/biossíntese , Homeostase , Peróxido de Hidrogênio/farmacologia , Metaloproteínas/biossíntese , Metais Pesados/toxicidade , Estresse Oxidativo , Oxilipinas , Fitoquelatinas , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/biossíntese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo
19.
Plant Mol Biol ; 36(5): 691-8, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9526501

RESUMO

Two cDNA clones which appear to encode different subunits of NAD(+)-dependent isocitrate dehydrogenase (IDH; EC 1.1.1.41) were identified by homology searches from the Arabidopsis EST database. These cDNA clones were obtained and sequenced; both encoded full-length messages and displayed 82.7% nucleotide sequence identity over the coding region. The deduced amino acid sequences revealed preprotein lengths of 367 residues, with an amino acid identity of 86.1%. Genomic Southern blot analysis showed distinct single-copy genes for both IDH subunits. Both IDH subunits were expressed as recombinant proteins in Escherichia coli, and polyclonal antibodies were raised to each subunit. The Arabidopsis cDNA clones were expressed in Saccharomyces cerevisiae mutants which were deficient in either one or both of the yeast NAD(+)-dependent IDH subunits. The Arabidopsis cDNA clones failed to complement the yeast mutations; although both IDH-I and IDH-II were expressed at detectable levels, neither protein was imported into the mitochondria.


Assuntos
Arabidopsis/enzimologia , Arabidopsis/genética , Isocitrato Desidrogenase/química , Isocitrato Desidrogenase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA de Plantas/genética , Expressão Gênica , Vetores Genéticos , Dados de Sequência Molecular , Conformação Proteica , Homologia de Sequência de Aminoácidos
20.
Arch Biochem Biophys ; 348(1): 65-74, 1997 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9390175

RESUMO

A cDNA EST clone encoding the C-terminal portion of Arabidopsis thaliana fumarase was identified by homology analysis. A fragment of cDNA encoding the N-terminal region of fumarase was amplified from a cDNA library using PCR and cloned. Genomic DNA corresponding to the coding region of fumarase was amplified and cloned. Arabidopsis fumarase was expressed as a chimeric fusion protein and polyclonal antibodies were generated. Fumarase was purified to near-homogeneity (over 600-fold) from etiolated Pisum sativum mitochondria. The identification of fumarase was confirmed by a combination of immunoblot and N-terminal amino acid sequencing. Kinetic analysis of highly purified fumarase yielded a KM(malate) of 0.45 mM and a Vmax(malate) of 650 mumol of fumarate/min/ mg. The pea fumarase was inhibited by the alpha-keto acids pyruvate and alpha-ketoglutarate at low millimolar concentrations. Adenylates were highly inhibitory; the degree of this inhibition was reduced in the presence of Mg2+, suggesting that uncomplexed adenylates are the inhibitory species.


Assuntos
Arabidopsis/enzimologia , Fumarato Hidratase/metabolismo , Genes de Plantas , Pisum sativum/enzimologia , Sequência de Aminoácidos , Animais , Arabidopsis/genética , Sequência de Bases , Clonagem Molecular , Escherichia coli/enzimologia , Fumarato Hidratase/química , Fumarato Hidratase/isolamento & purificação , Humanos , Cinética , Mitocôndrias/enzimologia , Dados de Sequência Molecular , Ratos , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Solanum tuberosum , Suínos
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