Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Trends Plant Sci ; 27(2): 124-138, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34629220

RESUMO

Unlike plants that were domesticated to secure food, the domestication and breeding of ornamental plants are driven by aesthetic values. Here, we examine the major elements of the extended evolutionary synthesis (EES) theory that bridges the gap between the biology of ornamental plant domestication and the sociocultural motivations behind it. We propose that it involves specific elements of cumulative cultural evolution (CCE), plant gene-human culture coevolution (PGHCC), and niche construction (NC). Moreover, ornamental plant domestication represents an aesthetics-driven dimension of human niche construction that coevolved with socioeconomic changes and the adoption of new scientific technologies. Initially functioning as symbolic and aesthetic assets, ornamental plants became globally marketed material commodities as a result of the co-dependence of human CCE and prestige-competition motivations.


Assuntos
Evolução Cultural , Domesticação , Evolução Biológica , Estética , Humanos
2.
Trends Plant Sci ; 26(6): 546-559, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33483266

RESUMO

Growing global demands for food, bioenergy, and specialty products, along with the threat posed by various environmental changes, present substantial challenges for agricultural production. Agricultural biotechnology offers a promising avenue for meeting these challenges; however, ethical and sociocultural concerns must first be addressed, to ensure widespread public trust and uptake. To be effective, we need to develop solutions that are ethically responsible, socially responsive, relevant to people of different cultural and social backgrounds, and conveyed to the public in a convincing and straightforward manner. Here, we highlight how ethical approaches, principled decision-making strategies, citizen-stakeholder participation, effective science communication, and bioethics education should be used to guide responsible use of agricultural biotechnology.


Assuntos
Bioética , Biotecnologia , Agricultura
3.
Trends Biotechnol ; 37(11): 1217-1235, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31235329

RESUMO

Breeding crops for high yield and superior adaptability to new and variable climates is imperative to ensure continued food security, biomass production, and ecosystem services. Advances in genomics and phenomics are delivering insights into the complex biological mechanisms that underlie plant functions in response to environmental perturbations. However, linking genotype to phenotype remains a huge challenge and is hampering the optimal application of high-throughput genomics and phenomics to advanced breeding. Critical to success is the need to assimilate large amounts of data into biologically meaningful interpretations. Here, we present the current state of genomics and field phenomics, explore emerging approaches and challenges for multiomics big data integration by means of next-generation (Next-Gen) artificial intelligence (AI), and propose a workable path to improvement.


Assuntos
Produtos Agrícolas/genética , Melhoramento Vegetal/métodos , Inteligência Artificial , Biomassa , Clima , Mudança Climática , Ecossistema , Genômica/métodos , Genótipo , Humanos , Fenômica/métodos , Fenótipo
4.
Clin Rehabil ; 33(2): 345-356, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30255716

RESUMO

OBJECTIVES:: To trace the psychological mechanism underlying caregivers' emotional experience in prolonged disorders of consciousness, by examining the mediating role of boundary ambiguity in the relationship between ambiguous loss and grief. DESIGN:: Cross-sectional design. SETTING:: The Respiratory Rehabilitation Division of a long-term medical and rehabilitation institute. SUBJECTS:: A total of 64 primary caregivers (69% female) of patients in a vegetative state ( n = 49) or minimally conscious state ( n = 15), with a mean age of 55.5 (SD = 12.3) years. Participants were mostly the patient's children (62%) or partners (27%). The mean caregiving duration was 4.9 (SD = 5.1) years. MAIN MEASURES:: The Boundary Ambiguity Scale, the Revised Need for Closure Scale, an adapted version of the multifactor Two-Track Bereavement Questionnaire, and a sociodemographic questionnaire, which included items regarding caregiving: frequency of visits and perception of the patient's psychological presence. RESULTS:: (1) Caregivers' grief scores (total TTBQ: mean = 2.97; SD = 0.55) did not significantly differ from those exhibited by a normative bereavement sample. (2) Time since injury did not affect caregivers' grief scores (three-year cut-point; P > .05). (3) Mediation analyses revealed that boundary ambiguity (mean = 34.03; SD = 7.55) significantly mediates the relationship between need for closure ( B = .11; confidence interval (CI) = .04-.23) and grief; frequency of visits ( B = .05, CI = .02-.10) and grief and perception of psychological presence ( B = .26, CI = .00-.61) and grief in three separate models. CONCLUSION:: Ambiguity concerning relational boundaries hinders caregivers' ongoing grief reaction and impedes their ability to integrate the loss. High frequency of visits, belief in the patient's psychological presence and difficulties in tolerating uncertainty are all clinical manifestations of caregivers' entangled experience.


Assuntos
Cuidadores/psicologia , Pesar , Estado Vegetativo Persistente/psicologia , Adulto , Idoso , Estudos Transversais , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
5.
Oncotarget ; 7(14): 17885-95, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-26909604

RESUMO

BACKGROUND: The immune response plays a significant role in pericarditis, but the mechanisms of disease are poorly defined. Further, efficient monitoring and predictive clinical tools are unavailable. Carcinoembryonic antigen cell adhesion molecule 1 (CEACAM1) is an immune-inhibitory protein, while MHC class I chain related protein A (MICA) and B (MICB) have an immune-stimulating function. METHODS AND RESULTS: Serum CEACAM1, MICA and MICB concentrations were measured by ELISA in ~50 subjects of each group: acute pericarditis (AP), recurrent pericarditis (RP) and lupus (SLE) patients, metastatic melanoma patients as well as healthy donors. Serum CEACAM1 was dramatically elevated in AP and RP patients, but not in SLE patients, and displayed a highly accurate profile in ROC curve analyses. MICA and MICB were elevated in some pericarditis patients. All markers were enhanced in metastatic melanoma patients irrespective of neoplastic pericardial involvement. Etiology-guided analysis of RP patients showed that very low MICA levels were associated with idiopathic RP, while high MICA was associated with autoimmune and post-operative RP. Importantly, MICA was significantly associated with recurrences, independently of other potentially confounding parameters such as age, time of follow up or treatment modality. CONCLUSIONS: Here we report for the first time on CEACAM1 as a potentially novel biomarker for pericarditis, as well as on MICA as an innovative prognostic marker in these patients. Determination of the roles of these immune factors, as well as their diagnostic and prognostic values should be determined in future prospective studies.


Assuntos
Biomarcadores Tumorais/sangue , Moléculas de Adesão Celular/sangue , Antígenos de Histocompatibilidade Classe I/sangue , Imunoglobulinas/sangue , Pericardite/sangue , Molécula 1 de Adesão Celular , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
6.
Trends Biotechnol ; 33(6): 337-42, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25842169

RESUMO

Advances in understanding plant biology, novel genetic resources, genome modification, and omics technologies generate new solutions for food security and novel biomaterials production under changing environmental conditions. New gene and germplasm candidates that are anticipated to lead to improved crop yields and other plant traits under stress have to pass long development phases based on trial and error using large-scale field evaluation. Therefore, quantitative, objective, and automated screening methods combined with decision-making algorithms are likely to have many advantages, enabling rapid screening of the most promising crop lines at an early stage followed by final mandatory field experiments. The combination of novel molecular tools, screening technologies, and economic evaluation should become the main goal of the plant biotechnological revolution in agriculture.


Assuntos
Agricultura/tendências , Biotecnologia/métodos , Plantas Geneticamente Modificadas/genética , Produtos Agrícolas/genética , Abastecimento de Alimentos/métodos , Genoma de Planta , Humanos
7.
Tree Physiol ; 34(11): 1181-98, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24695726

RESUMO

Abiotic stresses, such as drought, salinity and cold, are the major environmental stresses that adversely affect tree growth and, thus, forest productivity, and play a major role in determining the geographic distribution of tree species. Tree responses and tolerance to abiotic stress are complex biological processes that are best analyzed at a systems level using genetic, genomic, metabolomic and phenomic approaches. This will expedite the dissection of stress-sensing and signaling networks to further support efficient genetic improvement programs. Enormous genetic diversity for stress tolerance exists within some forest-tree species, and due to advances in sequencing technologies the molecular genetic basis for this diversity has been rapidly unfolding in recent years. In addition, the use of emerging phenotyping technologies extends the suite of traits that can be measured and will provide us with a better understanding of stress tolerance. The elucidation of abiotic stress-tolerance mechanisms will allow for effective pyramiding of multiple tolerances in a single tree through genetic engineering. Here we review recent progress in the dissection of the molecular basis of abiotic stress tolerance in forest trees, with special emphasis on Populus, Pinus, Picea, Eucalyptus and Quercus spp. We also outline practices that will enable the deployment of trees engineered for abiotic stress tolerance to land owners. Finally, recommendations for future work are discussed.


Assuntos
Adaptação Fisiológica , Regulação da Expressão Gênica de Plantas , Variação Genética , Magnoliopsida/fisiologia , Biomassa , Secas , Epigenômica , Florestas , Redes Reguladoras de Genes , Engenharia Genética , Genômica , Magnoliopsida/genética , Magnoliopsida/crescimento & desenvolvimento , Fenótipo , Transdução de Sinais , Estresse Fisiológico , Transgenes , Árvores/genética , Árvores/crescimento & desenvolvimento , Árvores/fisiologia
8.
J Clin Immunol ; 33 Suppl 1: S27-32, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23229779

RESUMO

During the last decade it has been shown that some components of intravenous immunoglobulin (IVIG) are responsible for their broadly therapeutic application. Currently, such specific subfractions are defined as specific IVIG (sIVIG) and are affinity-purified from commercial IVIGs that target specific antigens/antibodies related to a specific autoimmune disease. A remarkable example of the therapeutic potential of sIVIG is the proven enhanced anti-inflammatory potency of sialylated and recombinant sialylated IVIG obtained from total IVIG. In other experimental models, it has also been demonstrated that sIVIG work in many other contrivances, such as revealing anti-idiotypic networks blocking pathogenic antibodies ameliorating disease activity. sIVIG has also been shown to exert its action by modulating specific receptors expressed on immune cells in both inflammatory and autoimmune diseases. Indeed, sIVIG has emerged as a novel approach to treat different immune-mediated conditions in a more accurate antigen-specific manner. Herein we review experimental evidence supporting sIVIG-efficacy in treating autoimmune diseases and inflammation.


Assuntos
Imunoglobulinas Intravenosas/imunologia , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/imunologia , Fatores Imunológicos/uso terapêutico , Animais , Anti-Inflamatórios/imunologia , Anti-Inflamatórios/uso terapêutico , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Anti-Idiotípicos/uso terapêutico , Autoantígenos/imunologia , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Humanos
10.
Rev. bras. reumatol ; 52(3): 312-318, maio-jun. 2012. tab
Artigo em Português | LILACS | ID: lil-624871

RESUMO

INTRODUÇÃO: A associação entre infecções e doenças autoimunes (DAIs) está bem descrita na literatura médica. Vários agentes infecciosos foram implicados como indutores de respostas autoimunes, tais como o parvovírus B19, o vírus Epstein-Barr, o citomegalovírus e os vírus da hepatite. PACIENTES E MÉTODOS: Foram examinamos 1.173 soros de pacientes com 14 doenças autoimunes diferentes e 238 soros de controles saudáveis pareados geograficamente na busca por evidência de infecção rubeólica prévia. Todas as amostras foram testadas para a presença de anticorpos séricos contra rubéola usando-se o sistema Bio-Rad BioPlex 2200. RESULTADOS: Como um grupo, os pacientes com DAIs apresentaram maior prevalência de anticorpos IgM antirrubéola em comparação aos controles saudáveis (11,7% versus 5,4%; P = 0,001). A prevalência de anticorpos IgM antirrubéola foi significativamente maior em 5/14 DAIs, a saber: arterite de células gigantes (33,3%), cirrose biliar primária (24%), síndrome antifosfolipídica (20,6%), polimiosite (16%) e doença intestinal inflamatória (16%). Detectou-se prevalência semelhante de anticorpos IgM antirrubéola nos controles de diferentes países. Detectou-se alta prevalência de anticorpos IgG antirrubéola em pacientes com DAIs (89,9%) e controles. CONCLUSÃO: A prevalência aumentada de anticorpos IgM antirrubéola em DAIs sugere que a rubéola possa desempenhar um papel na etiopatogênese de várias DAIs.


INTRODUCTION: The association between infections and autoimmune diseases (AID) has been well described in the medical literature. Several infectious agents have been implicated as inducers of autoimmune responses, such as Parvovirus B19, Epstein-Barr virus, cytomegalovirus, and hepatitis viruses. PATIENTS AND METHODS: We examined 1,173 sera from patients with 14 different AID and 238 sera from geographically matched healthy controls, for evidence of prior infection with rubella. All samples were tested for the presence of serum antibodies against rubella using the Bio-Rad BioPlex 2200 system. RESULTS: As a group, patients with AID had a higher prevalence of IgM anti-rubella antibodies as compared to healthy controls (11.7% versus 5.4%; P = 0.001). The prevalence of IgM anti-rubella antibodies was significantly higher in 5/14 AID, namely in patients with giant cell arteritis (33.3%), primary biliary cirrhosis (24%), antiphospholipid syndrome (20.6%), polymyositis (16%), and inflammatory bowel disease (16%). A similar prevalence of IgM anti-rubella antibodies was detected among controls from different countries. A high prevalence of IgG anti-rubella antibodies was detected among patients with AID (89.9%) and controls. CONCLUSION: The increased prevalence of IgM anti-rubella antibodies in AID suggests a possible role for rubella in the etiopathogenesis of several AID.


Assuntos
Humanos , Anticorpos Antivirais/sangue , Doenças Autoimunes/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Rubéola (Sarampo Alemão)/sangue , Prevalência , Rubéola (Sarampo Alemão)/epidemiologia , Rubéola (Sarampo Alemão)/imunologia
11.
Rev Bras Reumatol ; 52(3): 307-18, 2012.
Artigo em Inglês, Português | MEDLINE | ID: mdl-22641586

RESUMO

INTRODUCTION: The association between infections and autoimmune diseases (AID) has been well described in the medical literature. Several infectious agents have been implicated as inducers of autoimmune responses, such as Parvovirus B19, Epstein-Barr virus, cytomegalovirus, and hepatitis viruses. PATIENTS AND METHODS: We examined 1,173 sera from patients with 14 different AID and 238 sera from geographically matched healthy controls, for evidence of prior infection with rubella. All samples were tested for the presence of serum antibodies against rubella using the Bio-Rad BioPlex 2200 system. RESULTS: As a group, patients with AID had a higher prevalence of IgM anti-rubella antibodies as compared to healthy controls (11.7% versus 5.4%; P = 0.001). The prevalence of IgM anti-rubella antibodies was significantly higher in 5/14 AID, namely in patients with giant cell arteritis (33.3%), primary biliary cirrhosis (24%), antiphospholipid syndrome (20.6%), polymyositis (16%), and inflammatory bowel disease (16%). A similar prevalence of IgM anti-rubella antibodies was detected among controls from different countries. A high prevalence of IgG anti-rubella antibodies was detected among patients with AID (89.9%) and controls. CONCLUSION: The increased prevalence of IgM anti-rubella antibodies in AID suggests a possible role for rubella in the etiopathogenesis of several AID.


Assuntos
Anticorpos Antivirais/sangue , Doenças Autoimunes/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Rubéola (Sarampo Alemão)/sangue , Humanos , Prevalência , Rubéola (Sarampo Alemão)/epidemiologia , Rubéola (Sarampo Alemão)/imunologia
12.
Rev Bras Reumatol ; 52(3): 305-6, 2012.
Artigo em Inglês, Português | MEDLINE | ID: mdl-22641585
13.
Am J Clin Exp Immunol ; 1(1): 49-55, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23885314

RESUMO

BACKGROUND: Gastrointestinal (GI)-related autoantibodies (Abs) are rarely evaluated in autoimmune diseases (AID) other than inflammatory bowel disease, autoimmune hepatitis and celiac disease. Our aim was to determine the prevalence of these antibodies in a wide spectrum of AID. METHODS: We examined 923 serum samples representing 18 AID and compared them with 338 samples from healthy subjects. We used the BioPlex 2200-immunoassay (Bio-Rad, USA) to test samples for the presence of IgA and IgG directed at gliadin (AGA), tissue-transglutaminase (tTG), and Saccharomyces cerevisiae (ASCA). RESULTS: Prevalence of IgA AGA was significantly higher in antiphospholipid syndrome (APS) (7.1 %, P=0.012) and in pemphigus vulgaris (25%, P =0.008) patients, as compared with healthy controls. Presence of IgG-AGA was more common among Crohn's disease (20.5%, P = 0.023) and rheumatoid arthritis (6.5%, P=0.027) patients. IgG anti tTG were frequently observed in APS (6.1%, P=0.012), in giant cell arteritis (11.5%, P=0.013) and in ulcerative colitis (11.1%, P=0.018) patients, and as expected, higher prevalence of ASCA (IgA 19.3% and IgG 27.7%) was found in Crohn's disease. IgG ASCA were also found in systemic lupus erythematosus (SLE) (4.5%, P=0.01), in Graves' disease (5.7%, P=0.018), in cryoglobulinemia (7.1%, P=0.006), and in patients with vasculitides (6.5%, P=0.002). In contrast, lower prevalence of IgG type AGA was found in SLE (P=0.034), cryoglobulinemia (P=0.019) and vasculitides (P=0.013) patients. CONCLUSIONS: Our findings suggest an association between GI-related- Abs and a wide spectrum of AID. The clinical implication of these findings is yet to be determined.

15.
J Patient Saf ; 7(4): 181-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21926639

RESUMO

OBJECTIVES: To perform initial validation of a continuous motion monitoring technology that can potentially be used as a risk assessment tool to determine risk for developing pressure ulcers (PUs). METHODS: We have used the EverOn system (Earlysense LTD, Ramat Gan, Israel) as a bed movement and activity monitor. The EverOn is a contactless continuous measurement system based on a piezoelectric sensor that is placed under the patient's mattress. The study was a noninterventional study performed in 2 medical departments in 2 medical centers. Recorded movement data from enrolled patients were retrospectively analyzed, and patients were assigned a motion level score. Motion scores for the first night of hospitalization were correlated with the Norton scale as calculated per patient on admission. RESULTS: Overall, 116 patients were included in the study from the 2 sites. Motion score was significantly different between the PU risk groups as determined by the Norton scale (10.7 ± 6.2 for low, 5.4 ± 4.9 for intermediate, and 1.6 ± 3.2 for high risk; P < 0.001). Using the Norton scale as a gold standard to define high risk for developing PU (≤14), the sensitivity of the motion score was 85%, and the specificity was 93%. With regard to individual risk components, we found that activity, mobility, physical condition, and incontinence correlated highly with motion level. CONCLUSIONS: The high correlation between the EverOn motion score and the calculated Norton scale indicates the potential of this technology to serve as a risk assessment tool for the development of PUs.


Assuntos
Movimento , Úlcera por Pressão/prevenção & controle , Medição de Risco/métodos , Idoso , Índice de Massa Corporal , Estudos de Viabilidade , Feminino , Humanos , Masculino , Úlcera por Pressão/etiologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Estatísticas não Paramétricas
16.
J Cardiovasc Nurs ; 26(6): 524-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21372731

RESUMO

Takotsubo cardiomyopathy (TC) is a neurocardiological disorder presumed to be triggered by stress, which may cause reversible heart failure, usually in postmenopausal women. It may mimic an acute myocardial infarction, accompanied by minimal elevation of cardiac enzymes, usually without evidence of obstructive coronary artery disease. Most clinicians are unfamiliar with this disorder. Therefore, some TCs are misdiagnosed as acute myocardial infarction. The modified Mayo Clinic criteria usually confirm a diagnosis, although the diagnostic criteria for TC remain controversial. Enhanced awareness by clinicians is important when encountering patients with chest pain and elevated cardiac enzymes. Takotsubo cardiomyopathy is usually associated with a favorable prognosis, although in rare instances it may be associated with life-threatening complications. Supportive care is especially important in the TC management. Our aim was to describe TC, characterize its clinical features, and extensively review the relevant literature.


Assuntos
Infarto do Miocárdio/diagnóstico , Cardiomiopatia de Takotsubo/diagnóstico , Fármacos Cardiovasculares/uso terapêutico , Dor no Peito/etiologia , Diagnóstico Diferencial , Diagnóstico por Imagem , Eletrocardiografia , Humanos , Prognóstico , Choque Cardiogênico/terapia , Estresse Psicológico/fisiopatologia , Cardiomiopatia de Takotsubo/fisiopatologia , Cardiomiopatia de Takotsubo/terapia , Troponina/sangue
17.
Cell Mol Immunol ; 8(3): 199-202, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21317916

RESUMO

The thymus is a central lymphatic organ that is responsible for many immunological functions, including the production of mature, functional T cells and the induction of self-tolerance. Benign or malignant tumors may originate from the thymus gland, with thymoma being the most common and accounting for 50% of anterior mediastinal tumors. Malignancies linked to thymoma include the loss of self-tolerance and the presence of autoimmunity. In this review, we compiled the current scientific evidence detailing the various interactions between thymoma and autoimmune diseases, including myasthenia gravis, systemic lupus erythematosus, inappropriate antidiuretic hormone secretion, pure red cell aplasia, pernicious anemia, pemphigus and autoimmune thyroid diseases. In recent years, several mechanisms have been proposed to explain these interactions. Most are based on the assumption that the 'sick' thymus, like the 'normal' thymus, can generate mature T cells; however, the T cells generated by the sick thymus are impaired and thus may exert cellular autoreactivity. Here, we present several theories that may shed light on the loss of self-tolerance associated with this epithelial tumor of the thymus.


Assuntos
Doenças Autoimunes/imunologia , Linfócitos T/imunologia , Timoma/imunologia , Timo/imunologia , Neoplasias do Timo/imunologia , Animais , Doenças Autoimunes/patologia , Autoimunidade , Diferenciação Celular , Humanos , Tolerância a Antígenos Próprios , Linfócitos T/patologia , Timoma/patologia , Neoplasias do Timo/patologia
18.
Trends Biotechnol ; 29(1): 9-17, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20970211

RESUMO

Forest trees provide raw materials, help to maintain biodiversity and mitigate the effects of climate change. Certain tree species can also be used as feedstocks for bioenergy production. Achieving these goals may require the introduction or modified expression of genes to enhance biomass production in a sustainable and environmentally responsible manner. Tree genetic engineering has advanced to the point at which genes for desirable traits can now be introduced and expressed efficiently; examples include biotic and abiotic stress tolerance, improved wood properties, root formation and phytoremediation. Transgene confinement, including flowering control, may be needed to avoid ecological risks and satisfy regulatory requirements. This and stable expression are key issues that need to be resolved before transgenic trees can be used commercially.


Assuntos
Engenharia Genética , Plantas Geneticamente Modificadas/genética , Árvores/genética , Animais , Biomassa , Ecossistema , Agricultura Florestal , Estresse Fisiológico
19.
Plant Physiol ; 154(4): 1697-709, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20959419

RESUMO

To investigate early salt acclimation mechanisms in a salt-tolerant poplar species (Populus euphratica), the kinetics of molecular, metabolic, and physiological changes during a 24-h salt exposure were measured. Three distinct phases of salt stress were identified by analyses of the osmotic pressure and the shoot water potential: dehydration, salt accumulation, and osmotic restoration associated with ionic stress. The duration and intensity of these phases differed between leaves and roots. Transcriptome analysis using P. euphratica-specific microarrays revealed clusters of coexpressed genes in these phases, with only 3% overlapping salt-responsive genes in leaves and roots. Acclimation of cellular metabolism to high salt concentrations involved remodeling of amino acid and protein biosynthesis and increased expression of molecular chaperones (dehydrins, osmotin). Leaves suffered initially from dehydration, which resulted in changes in transcript levels of mitochondrial and photosynthetic genes, indicating adjustment of energy metabolism. Initially, decreases in stress-related genes were found, whereas increases occurred only when leaves had restored the osmotic balance by salt accumulation. Comparative in silico analysis of the poplar stress regulon with Arabidopsis (Arabidopsis thaliana) orthologs was used as a strategy to reduce the number of candidate genes for functional analysis. Analysis of Arabidopsis knockout lines identified a lipocalin-like gene (AtTIL) and a gene encoding a protein with previously unknown functions (AtSIS) to play roles in salt tolerance. In conclusion, by dissecting the stress transcriptome of tolerant species, novel genes important for salt endurance can be identified.


Assuntos
Adaptação Fisiológica/genética , Perfilação da Expressão Gênica , Genes de Plantas , Populus/fisiologia , Cloreto de Sódio/metabolismo , Estresse Fisiológico/genética , Cromatografia Gasosa-Espectrometria de Massas , Técnicas de Inativação de Genes , Cinética , Pressão Osmótica , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Populus/genética
20.
J Agric Food Chem ; 58(12): 7158-65, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20443568

RESUMO

Cyanidin-3-rhamnoglucoside (C3R) is the major anthocyanin in fresh fig fruits. In this study, the free radical scavenging potential of C3R was evaluated in vitro using several free radical generators. This naturally occurring anthocyanin was superior to other tested natural antioxidants in scavenging ABTS(*+). Electron paramagnetic resonance served to determine the scavenging properties of C3R toward superoxide radical anion (O(2)(*-)), hydroxyl radical ((*)OH), and singlet radical ((1)O(2)). The protection of NIH-3T3 fibroblast cells was then tested as the inhibition of reactive oxygen species (ROS) formation in a dose-dependent manner. It was further demonstrated that treatment with C3R elevates the reduced glutathione (GSH) concentration and the redox ratio (GSH/GSSG) in fibroblast cells in a dose-dependent manner. Moreover, C3R reduced the induction of ROS by butathionine sulfoximine (BSO) and elevated the redox ratio. Thus, it is suggested that C3R in fresh fig fruits is a potent scavenger and may influence endogenous antioxidant systems of consumers.


Assuntos
Antocianinas/farmacologia , Fibroblastos/metabolismo , Ficus/química , Sequestradores de Radicais Livres/farmacologia , Glutationa/metabolismo , Radical Hidroxila/metabolismo , Extratos Vegetais/farmacologia , Animais , Antocianinas/análise , Antocianinas/isolamento & purificação , Espectroscopia de Ressonância de Spin Eletrônica , Fibroblastos/química , Fibroblastos/efeitos dos fármacos , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/isolamento & purificação , Frutas/química , Radical Hidroxila/análise , Camundongos , Células NIH 3T3 , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...