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1.
J Exp Bot ; 66(10): 2945-55, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25873657

RESUMO

In plants, the presence of thioredoxin (Trx), peroxiredoxin (Prx), and sulfiredoxin (Srx) has been reported as a component of a redox system involved in the control of dithiol-disulfide exchanges of target proteins, which modulate redox signalling during development and stress adaptation. Plant thiols, and specifically redox state and regulation of thiol groups of cysteinyl residues in proteins and transcription factors, are emerging as key components in the plant response to almost all stress conditions. They function in both redox sensing and signal transduction pathways. Scarce information exists on the transcriptional regulation of genes encoding Trx/Prx and on the transcriptional and post-transcriptional control exercised by these proteins on their putative targets. As another point of control, post-translational regulation of the proteins, such as S-nitrosylation and S-oxidation, is of increasing interest for its effect on protein structure and function. Special attention is given to the involvement of the Trx/Prx/Srx system and its redox state in plant signalling under stress, more specifically under abiotic stress conditions, as an important cue that influences plant yield and growth. This review focuses on the regulation of Trx and Prx through cysteine S-oxidation and/or S-nitrosylation, which affects their functionality. Some examples of redox regulation of transcription factors and Trx- and Prx-related genes are also presented.


Assuntos
Fenômenos Fisiológicos Vegetais , Proteínas de Plantas/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Oxirredução , Oxirredutases atuantes sobre Doadores de Grupo Enxofre/metabolismo , Peroxirredoxinas/metabolismo , Tiorredoxinas/metabolismo
2.
Neurologia (Engl Ed) ; 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37419211

RESUMO

BACKGROUND: Different types of therapies were proven effective for the medical management of motor and non-motor symptoms in Parkinson's disease (PD). We aimed to gain consensus on the dopamine agonist (DA) therapy use in different clinical scenarios of Parkinson's disease (PD) patients. METHODS: This consensus study was based on the nominal group technique. Initially, a consensus group comprising 12 expert neurologists in the PD field identified the topics to be addressed and elaborated different evidence-based preliminary statements. Next, a panel of 48 Spanish neurologists expressed their opinion on an internet-based systematic voting program. Finally, initial ideas were reviewed and rewritten according to panel contribution and were ranked by the consensus group using a Likert-type scale. The analysis of data was carried out by using a combination of both qualitative and quantitative methods. The consensus was achieved if the statement reached ≥ 3.5 points in the voting process. RESULTS: The consensus group produced 76 real-world recommendations. The topics addressed included 12 statements related to DA therapy in early PD, 20 statements concerning DA treatment strategy in patients with motor complications, 11 statements associated with DA drugs and their side effects, and 33 statements regarding DA therapy in specific clinical scenarios. The consensus group did not reach a consensus on 15 statements. CONCLUSION: The findings from this consensus method represent an exploratory step to help clinicians and patients in the appropriate use of DA in different stages and clinical situations of PD.

3.
J Exp Bot ; 63(15): 5487-96, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22915745

RESUMO

The present study was carried out to investigate the role of reactive oxygen species (ROS) metabolism in symptom development and pathogenesis in Nicotiana benthamiana plants upon infection with two strains of Pepper mild mottle virus, the Italian (PMMoV-I) and the Spanish (PMMoV-S) strains. In this host, it has been shown that PMMoV-I is less virulent and plants show the capability to recover 21 d after inoculation. Analyses of oxidative stress biomarkers, ROS-scavenging enzyme activities, and antioxidant compounds were conducted in plants at different post-infection times. Only PMMoV-I stimulated a defence response through: (i) up-regulation of different superoxide dismutase isozymes; (ii) maintenance of adequate levels of three peroxiredoxins (2-Cys Prx, Prx IIC, and Prx IIF); and (iii) adjustments in the glutathione pool to maintain the total glutathione content. Moreover, there was an increase in the level of oxidized glutathione and ascorbate in the recovery phase of PMMoV-I-infected plants. The antioxidant response and the extent of oxidative stress in N. benthamiana plants correlates to: (i) the severity of the symptoms elicited by either strain of PMMoV; and (ii) the high capacity of PMMoV-I-infected plants for symptom recovery and delayed senescence, compared with PMMoV-S-infected plants.


Assuntos
Antioxidantes/metabolismo , Regulação Enzimológica da Expressão Gênica/fisiologia , Nicotiana/fisiologia , Doenças das Plantas/virologia , Espécies Reativas de Oxigênio/metabolismo , Tobamovirus/patogenicidade , Ácido Ascórbico/análise , Ácido Ascórbico/metabolismo , Senescência Celular , Regulação da Expressão Gênica de Plantas/fisiologia , Glutationa/análise , Glutationa/metabolismo , Interações Hospedeiro-Patógeno , Isoenzimas , Estresse Oxidativo/fisiologia , Peroxirredoxinas/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/enzimologia , Folhas de Planta/fisiologia , Folhas de Planta/virologia , Superóxido Dismutase/metabolismo , Nicotiana/enzimologia , Nicotiana/virologia , Regulação para Cima , Virulência
4.
Chemosphere ; 302: 134937, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35561768

RESUMO

The use of macrophytes has been proposed recently as a suitable option for the phytostabilization or rhizofiltration of soils or waters contaminated by trace elements. As one of the most representative species of this type of plant, common reed (Phragmites australis (Cav.) Trin. ex Steud.) has shown tolerance to high concentrations of potentially hazardous elements, as is the case of arsenic. However, a deeper knowledge of how these plants deal with this toxicity, including their oxidative response, is needed for the optimum utilization of this species in phytoremediation procedures. In fact, little is known about how common reed plants react to As toxicity or the tolerance limits and accumulation potential of this species. In this work, common reed plants were exposed to a range of As(V) mass concentrations (0.5-10 mg L-1) in a hydroponic experiment, and the performance of the plants (growth, photosynthetic pigments, and oxidative stress related parameters) was evaluated and related to the major As species present in the different parts of the plants. The plants did not show any apparent symptom of toxicity and no significant effects were found for any of the different plant parameters analyzed. Arsenic was mostly accumulated as As(III) in the roots of the plants, and almost no translocation to the aerial part of the plants was observed for any of the As species analyzed. Common reed has shown a high capacity for As accumulation in its roots with no signs of toxicity, despite small nutrient imbalances. Thus, it can be considered to be a good candidate for use in the rhizofiltration and phytostabilization of As contaminated waters and soils, respectively.


Assuntos
Arsênio , Arsênio/toxicidade , Biodegradação Ambiental , Estresse Oxidativo , Raízes de Plantas , Plantas , Poaceae , Solo
5.
J Comput Chem ; 32(5): 915-31, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20960438

RESUMO

Deriving mean residence times (MRTs) is an important task both in pharmacokinetics and in multicompartmental linear systems. Taking as starting point the analysis of MRTs in open or closed (Garcia-Meseguer et al., Bull Math Biol 2003, 65, 279) multicompartmental linear systems, we implement a versatile software, using the Visual Basic 6.0 language for MS-Windows, that is easy to use and with a user-friendly format for the input of data and the output of results. For any multicompartmental linear system of up to 512 compartments, whether closed or open, with traps or without traps and with zero input in one or more of the compartments, this software allows the user to obtain the symbolic expressions, in the most simplified form, and/or the numerical values of the MRTs in any of its compartments, in the entire system or in a part of the system. As far as we known from the literature, such a software has not been implemented before. The advantage of the present software is that it reduces on the work time needed and minimizes the human errors that are frequent in compartmental systems even those that are relatively staightforward. The software bioCelTer, along with instructions, can be downloaded from http://oretano.iele-ab.uclm.es/~fgarcia/bioCelTer/.


Assuntos
Modelos Lineares , Software , Cinética , Fatores de Tempo
6.
Acta Neurol Scand ; 124(4): 275-81, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21198450

RESUMO

OBJECTIVES - Determine whether bilateral subthalamic nucleus stimulation (STN-DBS) in Parkinson's disease (PD) is associated with an increase in neuropeptide Y (NPY) and/or resistance to inhibition by leptin in relation to post-surgery weight gain. MATERIALS AND METHODS - This prospective study included 20 patients who underwent bilateral STN-DBS and 17 who refused surgery. Data were obtained at baseline, 3 and 6 months on neurological and nutritional status, including determination of body mass index (BMI) and serum NPY and leptin levels. RESULTS - NPY and leptin levels changed over time, with a distinct pattern. The BMI increase at 6 months was greater in the surgical group (5.5 ± 6.3% vs 0.5 ± 3.5%; P = 0.035). Medical group exhibited a reduction in leptin level (-2.0 ± 4.3 ng/ml) and a consequent increase in NPY level (72.4 ± 58.7 pmol/ml). However, STN-DBS patients showed an increase in leptin (3.1 ± 5.0 ng/ml; P = 0.001 vs medical group) and also in NPY (12.1 ± 53.6 pmol/ml; P = 0.022 vs medical group) levels, which suggests resistance to inhibition by leptin. Rise in NPY level correlated with higher stimulation voltages. CONCLUSIONS - Bilateral STN-DBS causes disruption of the melanocortin system, probably related to diffusion of the electric current to the hypothalamus. This mechanism may in part explain the weight gain of patients with PD after surgery.


Assuntos
Terapia por Estimulação Elétrica/efeitos adversos , Leptina/sangue , Neuropeptídeo Y/sangue , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiologia , Aumento de Peso/fisiologia , Idoso , Índice de Massa Corporal , Feminino , Humanos , Masculino , Melanocortinas/metabolismo , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
7.
Neurologia (Engl Ed) ; 36(2): 149-158, 2021 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32718872

RESUMO

INTRODUCTION: The main challenge of Parkinson's disease in women of childbearing age is managing symptoms and drugs during pregnancy and breastfeeding. The increase in the age at which women are having children makes it likely that these pregnancies will become more common in future. OBJECTIVES: This study aims to define the clinical characteristics of women of childbearing age with Parkinson's disease and the factors affecting their lives, and to establish a series of guidelines for managing pregnancy in these patients. RESULTS: This consensus document was developed through an exhaustive literature search and a discussion of the available evidence by a group of movement disorder experts from the Spanish Society of Neurology. CONCLUSIONS: Parkinson's disease affects all aspects of sexual and reproductive health in women of childbearing age. Pregnancy should be well planned to minimise teratogenic risk. A multidisciplinary approach should be adopted in the management of these patients in order to take all relevant considerations into account.


Assuntos
Doença de Parkinson , Adolescente , Adulto , Consenso , Feminino , Humanos , Neurologia , Doença de Parkinson/tratamento farmacológico , Adulto Jovem
8.
Neurologia (Engl Ed) ; 36(2): 159-168, 2021 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32980194

RESUMO

INTRODUCTION: Many diseases associated with hyperkinetic movement disorders manifest in women of childbearing age. It is important to understand the risks of these diseases during pregnancy, and the potential risks of treatment for the fetus. OBJECTIVES: This study aims to define the clinical characteristics and the factors affecting the lives of women of childbearing age with dystonia, chorea, Tourette syndrome, tremor, and restless legs syndrome, and to establish guidelines for management of pregnancy and breastfeeding in these patients. RESULTS: This consensus document was developed through an exhaustive literature search and a discussion of the content by a group of movement disorder experts from the Spanish Society of Neurology. CONCLUSIONS: We must evaluate the risks and benefits of treatment in all women with hyperkinetic movement disorders, whether pre-existing or with onset during pregnancy, and aim to reduce effective doses as much as possible or to administer drugs only when necessary. In hereditary diseases, families should be offered genetic counselling. It is important to recognise movement disorders triggered during pregnancy, such as certain types of chorea and restless legs syndrome.


Assuntos
Transtornos dos Movimentos , Doença de Parkinson , Adolescente , Adulto , Coreia , Distonia , Feminino , Humanos , Transtornos dos Movimentos/tratamento farmacológico , Doença de Parkinson/tratamento farmacológico , Síndrome das Pernas Inquietas/tratamento farmacológico , Síndrome de Tourette , Adulto Jovem
9.
Neurol Perspect ; 1(2): 124-130, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-38620826

RESUMO

Introduction: The COVID-19 pandemic has transformed medical practice and severely disrupted the training of medical residents worldwide. The Spanish Society of Neurology conducted a study to assess its impact on the training of neurology residents in Spain. Methods: We performed a descriptive, cross-sectional study through a survey distributed by e-mail to all neurology residents belonging to the Society. The survey included questions on demographic variables, care activity, and personal and educational impact of the pandemic, as well as respondents' expectations for the future of their work in the post-pandemic era. Results: Of 422 surveys sent, we received a total of 152 responses (36%); 79 respondents (52%) were women and 73 (48%) were men. By year of residency, 51 respondents (33.6%) were in the fourth year, 45 (29.6%) in the third year, 28 (18.4%) in the second year, and 28 (18.4%) in the first year. A total of 139 respondents (90.8%) reported changes in hospital activity, and 126 (82.8%) considered the situation to have had a negative impact on their training, with 99 (64.7%) having lost non-recoverable rotations. Sixty-six percent of respondents (n=101) expressed a desire to extend their residency period. Conclusions: The pandemic has had an extremely severe impact on all areas of the health system, with trainee physicians being one of the most affected groups. Among neurology residents, the crisis has caused significant shortcomings in their training and clinical activities, through the suspension of specific rotations. A high percentage of respondents wished to extend the residency period.

10.
Heliyon ; 6(8): e04703, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32904218

RESUMO

Arsenic (As) uptake by plants is mainly carried out as arsenate (As(V)), whose chemical analogy with phosphate is largely responsible for its elevated toxicity. Arsenate is known to stimulate reactive oxygen species (ROS) formation in plants that provoke oxidative stress. This manuscript reports the results of a hydroponics study using rice (Oryza sativa L.) seedlings as a test plant, where the effects of increasing arsenate concentrations (0-10 mg L-1) on both lipid and protein oxidation, as well as As accumulation and speciation in plant roots and shoots were examined. Plant yield was negatively affected by increasing As concentration. Accumulation in plant roots was higher than in shoots at low arsenate doses (0.5-2.5 mg L-1), while root to shoot transport was drastically enhanced at the highest doses (5 and 10 mg L-1). Moreover, As(V) was the dominating species in the shoots and As(III) in the roots. Rice leaves in the 10 mg As L-1 treatment showed the highest lipid peroxidation damage (malondialdehyde concentration), whilst protein oxidation was not remarkably influenced by As dose. Lipid peroxidation seems to be therefore conditioned by As accumulation in rice plants, particularly by the presence of high As(V) concentrations in the aerial part of the plants as a consequence of unregulated translocation from roots to shoots above a threshold concentration (1.25-2.5 mg L-1) in the growing media. These results provide relevant information regarding As(V) toxic concentrations for rice plants, highlight the importance of major As species analysis in plant tissues regarding As toxicity and contribute to better understand plants response to elevated As concentrations in the growing media.

11.
Neurologia (Engl Ed) ; 35(5): 295-302, 2020 Jun.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32448674

RESUMO

INTRODUCTION: Ischaemic stroke has been reported in patients with COVID-19, particularly in more severe cases. However, it is unclear to what extent this is linked to systemic inflammation and hypercoagulability secondary to the infection. METHODS: We describe the cases of 4 patients with ischaemic stroke and COVID-19 who were attended at our hospital. Patients are classified according to the likelihood of a causal relationship between the hypercoagulable state and ischaemic stroke. We also conducted a review of studies addressing the possible mechanisms involved in the aetiopathogenesis of ischaemic stroke in these patients. RESULTS: The association between COVID-19 and stroke was probably causal in 2 patients, who presented cortical infarcts and had no relevant arterial or cardioembolic disease, but did show signs of hypercoagulability and systemic inflammation in laboratory analyses. The other 2 patients were of advanced age and presented cardioembolic ischaemic stroke; the association in these patients was probably incidental. CONCLUSIONS: Systemic inflammation and the potential direct action of the virus may cause endothelial dysfunction, resulting in a hypercoagulable state that could be considered a potential cause of ischaemic stroke. However, stroke involves multiple pathophysiological mechanisms; studies with larger samples are therefore needed to confirm our hypothesis. The management protocol for patients with stroke and COVID-19 should include a complete aetiological study, with the appropriate safety precautions always being observed.


Assuntos
Isquemia Encefálica/etiologia , Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , Acidente Vascular Cerebral/virologia , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus/isolamento & purificação , COVID-19 , Sistema Nervoso Central/virologia , Infecções por Coronavirus/sangue , Infecções por Coronavirus/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/virologia , Fatores de Risco , SARS-CoV-2 , Acidente Vascular Cerebral/sangue , Trombofilia/virologia
12.
Acta Neurol Belg ; 120(2): 295-301, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30406497

RESUMO

Deep brain stimulation (DBS) is used to treat movement disorders, severe psychiatric disorders, and neuropathic pain, among other diseases. Advanced neuroimaging techniques allow direct or indirect localization of the target site, which is verified in many centers by the intraoperative recording of unitary neuronal activity. Intraoperative image acquisition technology (e.g., O-Arm) is increasingly used for accurate electrode positioning throughout the surgery. The aim of our study is to analyze the initial experience of our team in the utilization of O-Arm for planning DBS and monitoring its precision and accuracy throughout the procedure. The study included 13 patients with movement disorders. All underwent DBS with the intraoperative O-arm image acquisition system (iCT) and Medtronic StealthStation S7 cranial planning system, placing a total of 25 electrodes. For each patient, we calculated the difference between real and theoretic x, y, z coordinates, using the paired Student's t test to evaluate absolute and directional differences and the one-sample Student's t test to analyze differences in Euclidean distances. No statistically significant differences were found in absolute, directional, or Euclidean distances between intended and actual x, y, and z coordinates, based on iCT scan. Our experience confirms that utilization of the O-Arm system in DBS provides accurate and precise verification of electrode placements throughout the procedure. Recent studies found no significant differences between iCT and postoperative MRI, the current gold standard. Further prospective studies are warranted to test the elimination of postoperative MRI when this system is used.


Assuntos
Estimulação Encefálica Profunda/métodos , Imageamento Tridimensional/métodos , Neuroimagem/instrumentação , Neuronavegação/métodos , Cirurgia Assistida por Computador/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Adolescente , Adulto , Distúrbios Distônicos/cirurgia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/cirurgia , Tremor/cirurgia
13.
Plant Biol (Stuttg) ; 11(4): 613-24, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19538399

RESUMO

Purification and characterisation of pepper (Capsicum annuum L) chloroplasts and chromoplasts isolated from commercial green, red and yellow mature fruits were undertaken. Induction of the synthesis of several antioxidants in organelles isolated from mature fruits was found. The ultrastructure of organelles and the presence and activity of SOD isozymes and enzymes involved in the ASC-GSH cycle, together with the non-enzymatic antioxidant content and some oxidative parameters, were analysed. It was found that lipids, rather than proteins, seem to be a target for oxidation in the chromoplasts. The ascorbate and glutathione contents were elicited during differentiation of chloroplasts into chromoplasts in both red and yellow fruits. The activity of SOD and of components of the ASC-GSH cycle was up-regulated, suggesting that these enzymes may play a role in the protection of plastids and could act as modulators of signal molecules such as O(2) ( -) and H(2)O(2) during fruit maturation. The presence of an Mn-SOD in chromoplasts isolated from yellow pepper fruits was also investigated in terms of structural and antioxidant differences between the two cultivars.


Assuntos
Antioxidantes/metabolismo , Capsicum/metabolismo , Cloroplastos/metabolismo , Frutas/metabolismo , Ácido Ascórbico/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Glutationa/metabolismo , Superóxido Dismutase/metabolismo
14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 79(5 Pt 1): 051115, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19518424

RESUMO

We propose a comprehensive dynamical model for cooperative motion of self-propelled particles, e.g., flocking, by combining well-known elements such as velocity-alignment interactions, spatial interactions, and angular noise into a unified Lagrangian treatment. Noise enters into our model in an especially realistic way: it incorporates correlations, is highly nonlinear, and it leads to a unique collective behavior. Our results show distinct stability regions and an apparent change in the nature of one class of noise-induced phase transitions, with respect to the mean velocity of the group, as the range of the velocity-alignment interaction increases. This phase-transition change comes accompanied with drastic modifications of the microscopic dynamics, from nonintermittent to intermittent. Our results facilitate the understanding of the origin of the phase transitions present in other treatments.

15.
Chemosphere ; 223: 223-231, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30784729

RESUMO

Trace element (TE)-contaminated soils require the improvement of their physico-chemical properties in order to allow their restoration through phytostabilization technologies. This study aimed to determine the usefulness of oxidative stress related parameters to validate the suitability of two different combinations of organic (solid fraction of pig slurry) and inorganic (paper mill sludge or a commercial red mud derivative) amendments for the phytostabilization of an acidic (4.2) TE-contaminated mine soil from SE Spain. Two wild species (Silybum marianum and Piptatherum miliaceum) were greenhouse cultivated and the development of the plants, their ionome, and oxidative stress related parameters were determined. Both amendment combinations increased significantly soil pH (to 5-6) and soil/pore water total organic C and total N concentrations, allowing an adequate plant growth and development (plants did not grow in untreated soils). The combination of amendments significantly reduced metal availability and showed to be effective (specially the one including the red mud derivative) in limiting shoot TE concentrations, which were all within common ranges (exclusion based tolerance of these species). Both protein carbonylation and lipid peroxidation were significantly higher in S. marianum plants from phytostabilized soils than in those from non-contaminated soils, which confirms the oxidative stress these plants suffer despite their satisfactory growth in the treated soils. P. miliaceum plants showed no differences between phytostabilized and non-contaminated soils. Therefore, the combination of amendments and TE-tolerant autochthonous species would be a suitable option for the phytostabilisation of soils contaminated by mining activities, reducing TE solubility and allowing an adequate plant growth.


Assuntos
Mineração , Estresse Oxidativo/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Solo/química , Oligoelementos/efeitos adversos , Animais , Compostos Inorgânicos/farmacologia , Compostos Orgânicos/farmacologia , Plantas/metabolismo , Poluentes do Solo/análise , Espanha , Suínos
17.
Neurocirugia (Astur) ; 17(4): 325-32, 2006 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-16960643

RESUMO

BACKGROUND: Based on earlier studies, we aimed to determine the quality of life of patients with intracranial aneurysm after their treatment by surgery or embolization and to compare the quality of life of these two groups. METHODS: The SF-36 health questionnaire was retrospectively applied to 93 patients with intracranial aneurysm treated with surgery (n=56) or embolization (n=37). RESULTS: The quality of life of some patients was impaired but 50% of patients treated with surgery and 40.5% of patients treated with embolization showed no impairment in any SF-36 domain. The quality of life in the Physical Functioning domain was higher in embolization-treated than in surgery-treated patients. CONCLUSIONS: Some patients with intracranial aneurysms treated with surgery or endovascular embolization have an impaired quality of life. Endovascular treatment may cause less limitation in physical function. The quality of life of these patients is affected by numerous factors, in addition to the type of treatment.


Assuntos
Embolização Terapêutica/efeitos adversos , Aneurisma Intracraniano , Procedimentos Neurocirúrgicos/efeitos adversos , Qualidade de Vida , Adulto , Idoso , Feminino , Humanos , Aneurisma Intracraniano/cirurgia , Aneurisma Intracraniano/terapia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
18.
Food Chem ; 194: 1064-72, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26471654

RESUMO

In non-photosynthetic tissues, mitochondria are the main source of energy and of reactive oxygen species. Accumulation of high levels of these species in the cell causes damage to macromolecules including several proteins and induces changes in different metabolic processes. Fruit ripening has been characterized as an oxidative phenomenon; therefore, control of reactive oxygen species levels by mitochondrial antioxidants plays a crucial role on this process. In this work, ascorbate-glutathione cycle components, hydrogen peroxide levels and the proteomic profile of carbonylated proteins were analyzed in mitochondria isolated from tomato (Solanum lycopersicum) fruit at two ripening stages. A significant increase on most ascorbate-glutathione cycle components and on carbonylated proteins was observed in mitochondria from breaker to light red stage. Enzymes and proteins involved in diverse cellular and mitochondrial metabolic pathways were identified among the carbonylated proteins. These results suggest that protein carbonylation is a post-translational modification involved in tomato fruit ripening regulation.


Assuntos
Ácido Ascórbico/química , Frutas/química , Mitocôndrias/química , Carbonilação Proteica , Solanum lycopersicum/química , Glutationa/metabolismo , Proteômica
19.
Biochim Biophys Acta ; 1548(1): 1-22, 2001 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-11451433

RESUMO

Tyrosinase can act on monophenols because of the mixture of met- (E(m)) and oxy-tyrosinase (E(ox)) which exists in the native form of the enzyme. The latter form is active on monophenols, while the former is not. However, the kinetics are complicated because monophenols can bind to both enzyme forms. This situation becomes even more complex since the products of the enzymatic reaction, the o-quinones, are unstable and continue evolving to generate o-diphenols in the medium. In the case of substrates such as L-tyrosine, tyrosinase generates very unstable o-quinones, in which a process of cyclation and subsequent oxidation-reduction generates o-diphenol through non-enzymatic reactions. However, the release of o-diphenol through the action of the enzyme on the monophenol contributes to the concentration of o-diphenol in the first pseudo-steady-state [D(0)](ss). Hence, the system reaches an initial pseudo-steady state when t-->0 and undergoes a transition phase (lag period) until a final steady state is reached when the concentration of o-diphenol in the medium reaches the concentration of the final steady state [D(f)](ss). These results can be explained by taking into account the kinetic and structural mechanism of the enzyme. In this, tyrosinase hydroxylates the monophenols to o-diphenols, generating an intermediate, E(m)D, which may oxidise the o-diphenol or release it directly to the medium. We surmise that the intermediate generated during the action of E(ox) on monophenols, E(m)D, has axial and equatorial bonds between the o-diphenol and copper atoms of the active site. Since the orbitals are not coplanar, the concerted oxidation-reduction reaction cannot occur. Instead, a bond, probably that of C-4, is broken to achieve coplanarity, producing a more labile intermediate that will then release the o-diphenol to the medium or reunite it diaxially, involving oxidation to o-quinone. The non-enzymatic evolution of the o-quinone would generate the o-diphenol ([D(f)](ss)) necessary for the final steady state to be reached after the lag period.


Assuntos
Agaricales/enzimologia , Monofenol Mono-Oxigenase/química , Fenóis/química , Quinonas/química , Catecol Oxidase/química , Relação Dose-Resposta a Droga , Cinética , Levodopa/química , Modelos Químicos , Modelos Teóricos , Monofenol Mono-Oxigenase/farmacologia , Espectrofotometria , Tirosina/química
20.
Plant Physiol ; 114(1): 275-284, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-12223704

RESUMO

The presence of the enzymes of the ascorbate-glutathione cycle was investigated in mitochondria and peroxisomes purified from pea (Pisum sativum L.) leaves. All four enzymes, ascorbate peroxidase (APX; EC 1.11.1.11), monodehydroascorbate reductase (EC 1.6.5.4), dehydroascorbate reductase (EC 1.8.5.1), and glutathione reductase (EC 1.6.4.2), were present in mitochondria and peroxisomes, as well as in the antioxidants ascorbate and glutathione. The activity of the ascorbate-glutathione cycle enzymes was higher in mitochondria than in peroxisomes, except for APX, which was more active in peroxisomes than in mitochondria. Intact mitochondria and peroxisomes had no latent APX activity, and this remained in the membrane fraction after solubilization assays with 0.2 M KCl. Monodehydroascorbate reductase was highly latent in intact mitochondria and peroxisomes and was membrane-bound, suggesting that the electron acceptor and donor sites of this redox protein are not on the external side of the mitochondrial and peroxisomal membranes. Dehydroascorbate reductase was found mainly in the soluble peroxisomal and mitochondrial fractions. Glutathione reductase had a high latency in mitochondria and peroxisomes and was present in the soluble fractions of both organelles. In intact peroxisomes and mitochondria, the presence of reduced ascorbate and glutathione and the oxidized forms of ascorbate and glutathione were demonstrated by high-performance liquid chromatography analysis. The ascorbate-glutathione cycle of mitochondria and peroxisomes could represent an important antioxidant protection system against H2O2 generated in both plant organelles.

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