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1.
Int J Mol Sci ; 24(12)2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37373458

RESUMO

Lettuce (Lactuca sativa L.) is one of the commercially important leafy vegetables worldwide. However, lettuce cultivars vary widely in their carotenoid concentrations at the time of harvest. While the carotenoid content of lettuce can depend on transcript levels of key biosynthetic enzymes, genes that can act as biomarkers for carotenoid accumulation at early stages of plant growth have not been identified. Transcriptomic and metabolomic analysis was performed on the inner and outer leaves of the six cultivars at different developmental stages to identify gene-to-metabolite networks affecting the accumulation of two key carotenoids, ß-carotene and lutein. Statistical analysis, including principal component analysis, was used to better understand variations in carotenoid concentration between leaf age and cultivars. Our results demonstrate that key enzymes of carotenoid biosynthesis pathway can alter lutein and ß-carotene biosynthesis across commercial cultivars. To ensure high carotenoids content in leaves, the metabolites sink from ß-carotene and lutein to zeaxanthin, and subsequently, abscisic acid needs to be regulated. Based on 2-3-fold carotenoids increase at 40 days after sowing (DAS) as compared to the seedling stage, and 1.5-2-fold decline at commercial stage (60 DAS) compared to the 40 DAS stage, we conclude that the value of lettuce for human nutrition would be improved by use of less mature plants, as the widely-used commercial stage is already at plant senescence stage where carotenoids and other essential metabolites are undergoing degradation.


Assuntos
Lactuca , beta Caroteno , Humanos , beta Caroteno/metabolismo , Lactuca/metabolismo , Luteína , Plântula/metabolismo , Carotenoides/metabolismo
2.
Plant Physiol ; 180(1): 109-123, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30755474

RESUMO

Green macroalgae of the genus Ulva play a key role in coastal ecosystems and are of increasing commercial importance. However, physiological differences between strains and species have yet to be described in detail. Furthermore, the strains of Ulva used in aquaculture usually originate from opportunistic collection in the wild without prior selection of best performing strains. Hence, efforts are required to detect the potential variability in growth and metabolic accumulation between Ulva strains and ultimately select the best performing strains under given environmental conditions. Here, the growth, physiological, and metabolic characteristics of 49 laminar Ulva spp. strains were investigated using a custom-made high-throughput phenotyping platform, enzymatic assays, and gas chromatography-mass spectrometry. We found large natural variation for a wide range of growth and metabolic characteristics, with growth rates varying from 0.09 to 0.37 mg.mg-1d-1 among strains. Ulva spp. possess a unique diurnal growth pattern and primary metabolism compared with land plants, with higher growth rates during the night than during the light period. Starch and sucrose only contributed on average 35% of the carbon required to sustain Ulva's night growth. Nitrates accumulated during the night in Ulva tissues, and nitrate accumulation and consumption was positively correlated with growth. In addition, we identified six amino acids as possible biomarkers for high growth in Ulva The large variability in growth and metabolite accumulation recorded among morphologically similar Ulva strains justifies future efforts in strain selection for increasing biomass, metabolite yields, and nutrient removal in the growing aquaculture industry.


Assuntos
Ritmo Circadiano , Ulva/crescimento & desenvolvimento , Aquicultura , Carbono/metabolismo , Estudo de Associação Genômica Ampla , Nitratos/metabolismo , Fenótipo , Filogenia , Ulva/genética , Ulva/metabolismo
3.
Plant Cell Environ ; 43(6): 1404-1420, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32012288

RESUMO

Barley is described to mostly use sucrose for night carbon requirements. To understand how the transient carbon is accumulated and utilized in response to cold, barley plants were grown in a combination of cold days and/or nights. Both daytime and night cold reduced growth. Sucrose was the main carbohydrate supplying growth at night, representing 50-60% of the carbon consumed. Under warm days and nights, starch was the second contributor with 26% and malate the third with 15%. Under cold nights, the contribution of starch was severely reduced, due to an inhibition of its synthesis, including under warm days, and malate was the second contributor to C requirements with 24-28% of the total amount of carbon consumed. We propose that malate plays a critical role as an alternative carbon source to sucrose and starch in barley. Hexoses, malate, and sucrose mobilization and starch accumulation were affected in barley elf3 clock mutants, suggesting a clock regulation of their metabolism, without affecting growth and photosynthesis however. Altogether, our data suggest that the mobilization of sucrose and malate and/or barley growth machinery are sensitive to cold.


Assuntos
Ritmo Circadiano/fisiologia , Temperatura Baixa , Escuridão , Hordeum/crescimento & desenvolvimento , Hordeum/fisiologia , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Clorofila/metabolismo , Fluorescência , Frutanos/metabolismo , Malatos/metabolismo , Metaboloma , Fotossíntese , Proteínas de Plantas/metabolismo , Estômatos de Plantas/fisiologia , Transpiração Vegetal/fisiologia , Solubilidade , Amido/metabolismo , Sacarose/metabolismo , Açúcares/metabolismo
4.
Crit Rev Microbiol ; 44(5): 541-560, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29528259

RESUMO

Cyanobacteria are one of the earliest branching groups of organisms on the planet, and during their evolutionary history were submitted to varying selective pressures. Nowadays, cyanobacteria can grow in a variety of conditions, using a large number of nitrogen sources. The control of the nitrogen metabolism in cyanobacteria depends on a fine-tuning regulatory network involving 2-oxoglutarate (2-OG), PII, PipX, and NtcA. This network answers to the cellular 2-OG levels, which reflects the cellular carbon/nitrogen balance, and as an output regulates gene expression, translation, protein activities and thus metabolic pathways. Hence, the diurnal regulation of growth may be directly dependent of this network, as it coordinates the use of photoassimilates towards either growth or the accumulation of reserves, based on the environmental conditions. Therefore, analysis of the nitrogen control network is not only important to comprehend the metabolic control of growth in cyanobacteria, but is also a target to improve cyanobacterial biotechnological potential. In this review, we discuss the mechanisms involved in the control of nitrogen metabolism and its potential role in the diurnal regulation of growth. Then, we highlight why a better understanding of the mechanisms involved in the partitioning of carbon and nitrogen towards growth or storage would increase the biotechnological potential of these organisms.


Assuntos
Cianobactérias/crescimento & desenvolvimento , Cianobactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Nitrogênio/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biotecnologia , Cianobactérias/genética
5.
Plant Physiol ; 174(4): 2166-2182, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28646084

RESUMO

Many studies have investigated the various genetic and environmental factors regulating cyanobacterial growth. Here, we investigated the growth and metabolism of Synechocystis sp. PCC 6803 under different nitrogen sources, light intensities, and CO2 concentrations. Cells grown on urea showed the highest growth rates. However, for all conditions tested, the daily growth rates in batch cultures decreased steadily over time, and stationary phase was obtained with similar cell densities. Unexpectedly, metabolic and physiological analyses showed that growth rates during log phase were not controlled primarily by the availability of photoassimilates. Further physiological investigations indicated that nutrient limitation, quorum sensing, light quality, and light intensity (self-shading) were not the main factors responsible for the decrease in the growth rate and the onset of the stationary phase. Moreover, cell division rates in fed-batch cultures were positively correlated with the dilution rates. Hence, not only light, CO2, and nutrients can affect growth but also a cell-cell interaction. Accordingly, we propose that cell-cell interaction may be a factor responsible for the gradual decrease of growth rates in batch cultures during log phase, culminating with the onset of stationary phase.


Assuntos
Divisão Celular , Synechocystis/citologia , Contagem de Células , Metaboloma , Fotossíntese , Característica Quantitativa Herdável , Percepção de Quorum , Estatísticas não Paramétricas , Synechocystis/crescimento & desenvolvimento , Synechocystis/metabolismo , Synechocystis/fisiologia
6.
Int J Syst Evol Microbiol ; 68(9): 2770-2782, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29985124

RESUMO

Cyanobacteria is an ancient phylum of oxygenic photosynthetic microorganisms found in almost all environments of Earth. In recent years, the taxonomic placement of some cyanobacterial strains, including those belonging to the genus Nostocsensu lato, have been reevaluated by means of a polyphasic approach. Thus, 16S rRNA gene phylogeny and 16S-23S internal transcribed spacer (ITS) secondary structures coupled with morphological, ecological and physiological data are considered powerful tools for a better taxonomic and systematics resolution, leading to the description of novel genera and species. Additionally, underexplored and harsh environments, such as saline-alkaline lakes, have received special attention given they can be a source of novel cyanobacterial taxa. Here, a filamentous heterocytous strain, Nostocaceae CCM-UFV059, isolated from Laguna Amarga, Chile, was characterized applying the polyphasic approach; its fatty acid profile and physiological responses to salt (NaCl) were also determined. Morphologically, this strain was related to morphotypes of the Nostocsensu lato group, being phylogenetically placed into the typical cluster of the genus Desmonostoc. CCM-UFV059 showed identity of the 16S rRNA gene as well as 16S-23S secondary structures that did not match those from known described species of the genus Desmonostoc, as well as distinct ecological and physiological traits. Taken together, these data allowed the description of the first strain of a member of the genus Desmonostoc from a saline-alkaline lake, named Desmonostoc salinum sp. nov., under the provisions of the International Code of Nomenclature for algae, fungi and plants. This finding extends the ecological coverage of the genus Desmonostoc, contributing to a better understanding of cyanobacterial diversity and systematics.


Assuntos
Cianobactérias/classificação , Lagos/microbiologia , Filogenia , Salinidade , Álcalis , Técnicas de Tipagem Bacteriana , Chile , Cianobactérias/genética , Cianobactérias/isolamento & purificação , DNA Bacteriano/genética , DNA Espaçador Ribossômico/genética , Ácidos Graxos/química , Concentração de Íons de Hidrogênio , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
Health Qual Life Outcomes ; 15(1): 157, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-28807029

RESUMO

BACKGROUND: The NEI VFQ-25 has undergone psychometric evaluation in patients with varying ocular conditions and the general population. However, important limitations which may affect the interpretation of clinical trial results have been previously identified, such as concerns with reliability and validity. The purpose of this study was to evaluate the National Eye Institute Visual Functioning Questionnaire (NEI VFQ-25) and make recommendations for a revised scoring structure, with a view to improving its psychometric performance and interpretability. METHODS: Rasch Measurement Theory analyses were conducted in two stages using pooled baseline NEI VFQ-25 data for 2487 participants with retinal diseases enrolled in six clinical trials. In stage 1, we examined: scale-to-sample targeting; thresholds for item response options; item fit statistics; stability; local dependence; and reliability. In stage 2, a post-hoc revision of the scoring structure (VFQ-28R) was created and psychometrically re-evaluated. RESULTS: In stage 1, we found that the NEI VFQ-25 was mis-targeted to the sample, and had disordered response thresholds (15/25 items) and mis-fitting items (8/25 items). However, items appeared to be stable (differential item functioning for three items), have minimal item dependency (one pair of items) and good reliability (person-separation index, 0.93). In stage 2, the modified Rasch-scored NEI VFQ-28-R was assessed. It comprised two broad domains: Activity Limitation (19 items) and Socio-Emotional Functioning (nine items). The NEI VFQ-28-R demonstrated improved performance with fewer disordered response thresholds (no items), less item misfit (three items) and improved population targeting (reduced ceiling effect) compared with the NEI VFQ-25. CONCLUSIONS: Compared with the original version, the proposed NEI VFQ-28-R, with Rasch-based scoring and a two-domain structure, appears to offer improved psychometric performance and interpretability of the vision-related quality of life scale for the population analysed.


Assuntos
Atividades Cotidianas , Algoritmos , National Eye Institute (U.S.) , Qualidade de Vida , Doenças Retinianas/psicologia , Inquéritos e Questionários/normas , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria , Reprodutibilidade dos Testes , Estados Unidos , Visão Ocular
8.
Genet Mol Biol ; 40(1 suppl 1): 261-275, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28323299

RESUMO

Cyanobacteria is a remarkable group of prokaryotic photosynthetic microorganisms, with several genera capable of fixing atmospheric nitrogen (N2) and presenting a wide range of morphologies. Although the nitrogenase complex is not present in all cyanobacterial taxa, it is spread across several cyanobacterial strains. The nitrogenase complex has also a high theoretical potential for biofuel production, since H2 is a by-product produced during N2 fixation. In this review we discuss the significance of a relatively wide variety of cell morphologies and metabolic strategies that allow spatial and temporal separation of N2 fixation from photosynthesis in cyanobacteria. Phylogenetic reconstructions based on 16S rRNA and nifD gene sequences shed light on the evolutionary history of the two genes. Our results demonstrated that (i) sequences of genes involved in nitrogen fixation (nifD) from several morphologically distinct strains of cyanobacteria are grouped in similarity with their morphology classification and phylogeny, and (ii) nifD genes from heterocytous strains share a common ancestor. By using this data we also discuss the evolutionary importance of processes such as horizontal gene transfer and genetic duplication for nitrogenase evolution and diversification. Finally, we discuss the importance of H2 synthesis in cyanobacteria, as well as strategies and challenges to improve cyanobacterial H2 production.

9.
BMC Med Res Methodol ; 14: 140, 2014 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-25533265

RESUMO

BACKGROUND: Two treatments, ranibizumab and dexamethasone implant, for visual impairment due to macular oedema (ME) secondary to retinal vein occlusion (RVO) have recently been studied in clinical trials. There have been no head to head comparisons of the two treatments, and improvement measured as gain in Best Corrected Visual Acuity (BCVA) was reported using different outcomes thresholds between trials. To overcome these limitations, and inform an economic model, we developed a combination of a multinomial model and an indirect Bayesian comparison model for multinomial outcomes. METHODS: Outcomes of change from baseline in BCVA for dexamethasone compatible with those available for ranibizumab, reported by 4 randomised controlled trials, were estimated by fitting a multinomial distribution model to the probability of a patient achieving outcomes in a range of changes from baseline in BCVA (numbers of letters) at month 1. A Bayesian indirect comparison multinomial model was then developed to compare treatments in the Branch RVO (BRVO) and Central RVO (CRVO) populations. RESULTS: The multinomial model had excellent fit to the observed results. With the Bayesian indirect comparison, the probabilities of achieving ≥20 letters, with 95% credible intervals, at month 1 in patients with BRVO were 0.191 (0.130, 0.261) with ranibizumab and 0.093 (0.027, 0.213) with dexamethasone. In patients with CRVO, probabilities were 0.133 (0.082, 0.195) (ranibizumab) and 0.063 (0.016, 0.153) (dexamethasone). Probabilities of a gain in ≥10 letters in BRVO patients were 0.500 (0.365, 0.650) v 0.459 (0.248, 0.724) and in CRVO patients 0.459 (0.332, 0.602) v 0.498 (0.263, 0.791) for ranibizumab and dexamethasone treatments respectively. The comparisons also favoured ranibizumab at month 6 although changes to therapies after month 3 may have introduced bias. CONCLUSION: The newly developed combination of multinomial and indirect Bayesian comparison models indicated a trend for ranibizumab association with a greater percentage of ME patients achieving visual gains than dexamethasone at months 1 and 6 in a common clinical context, although results were not classically significant. The method was a useful tool for comparisons of probability distributions between clinical trials that reported events on different categorical scales and estimates can be used to inform economic models.


Assuntos
Dexametasona/uso terapêutico , Edema Macular/tratamento farmacológico , Ranibizumab/uso terapêutico , Oclusão da Veia Retiniana/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Teorema de Bayes , Feminino , Humanos , Edema Macular/complicações , Masculino , Pessoa de Meia-Idade , Oclusão da Veia Retiniana/etiologia , Distribuições Estatísticas , Resultado do Tratamento , Acuidade Visual , Adulto Jovem
10.
BMC Ophthalmol ; 14: 7, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24447389

RESUMO

BACKGROUND: Macular oedema secondary to retinal vein occlusion (RVO) can cause vision loss due to blockage of the central retinal vein (CRVO) or a branch retinal vein (BRVO). This systematic review assessed the efficacies of widely used treatments for macular oedema secondary to RVO and the feasibility of conducting indirect comparisons between these therapies. METHODS: A systematic review was undertaken in November 2010, including a literature search for trials in medical databases and relevant websites. Abstracts, conference presentations and unpublished studies were considered. Studies were data-extracted and quality assessed by two independent researchers. Outcome measures included the mean change in best corrected visual acuity (BCVA) from baseline in the study eye and/or number of patients gaining at least 10 letters from baseline to 6 months or the nearest equivalent time point. RESULTS: Fourteen unique randomized controlled trials (RCTs) were identified. Ranibizumab 0.5 mg produced greater improvements in BCVA at 6 months than sham in BRVO (mean difference 11.0 letters, 95% confidence interval [CI] 7.83, 14.17) and CRVO (mean difference 14.10 letters, 95% CI 10.51, 17.69) in two double-blind sham-controlled RCTs. Pooled data from two double-blind, sham-controlled RCTs showed that improvements in BCVA were also significantly better for dexamethasone intravitreal (IVT) implant 0.7 mg compared with sham in patients with BRVO or CRVO (mean difference 2.5 letters, 95% CI 0.7, 4.3); the difference was significant for BRVO alone, but not CRVO alone. A significantly greater proportion of patients with BRVO gained ≥15 letters with laser therapy vs. no treatment at 36 months in a large prospective RCT (odds ratio 3.16, 95% CI 1.25, 8.00), whereas no difference was observed at 9 months in a smaller study. Three studies reported no benefit for laser therapy in CRVO. No indirect comparisons with ranibizumab were feasible due to differences in study design and baseline characteristics. CONCLUSIONS: Data from RCTs for ranibizumab and dexamethasone IVT demonstrate that both new agents constitute significant improvements over the previously widely accepted standard of care (laser therapy) for the treatment of BRVO and CRVO. However, head-to-head studies are needed to assess the relative efficacies of licensed therapies for RVO.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Dexametasona/uso terapêutico , Terapia a Laser , Edema Macular/terapia , Oclusão da Veia Retiniana/complicações , Humanos , Edema Macular/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Ranibizumab , Acuidade Visual
11.
Crit Care Med ; 41(1): 133-42, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23128383

RESUMO

OBJECTIVE: Dysnatremia may have an impact on outcomes in critically ill patients, but this has not been widely investigated in surgical ICU patients. We investigated the epidemiology of dysnatremia in a large cohort of surgical ICU patients and evaluated the possible influence of the time of acquisition of dysnatremia and fluctuations in serum sodium concentrations on hospital mortality in these patients. DESIGN: Retrospective analysis. SETTING: Fifty-bed surgical ICU. PATIENTS: All patients admitted to the ICU between January 2004 and January 2009. MEASUREMENTS AND MAIN RESULTS: Hyponatremia was defined as a serum sodium concentration <135 mmol/L and hypernatremia as a serum sodium concentration >145 mmol/L. Of the 10,923 surgical ICU patients included in the study, 1,215 (11.2%) had hyponatremia and 277 (2.5%) had hypernatremia at admission to the ICU. Among patients with normonatremia at admission to the ICU (n = 9431), the prevalence of ICU-acquired dysnatremia was 31.3%. Dysnatremia present at ICU admission (odds ratio 2.53; 95% confidence interval 2.06-3.12; p < .001) and ICU-acquired dysnatremia (odds ratio 2.06; 95% confidence interval 1.71-2.48; p < 0.001) were independently associated with an increased risk of in-hospital death compared to normonatremia. Dysnatremia at ICU admission (odds ratio 1.23; 95% confidence interval 1.01-1.50) was associated with a higher risk of in-hospital death, compared with ICU-acquired dysnatremia. Fluctuation in serum sodium concentration was also independently associated with an increased risk of in-hospital mortality, in patients who remained normonatremic (>6 mmol/L/ICU stay) and in those with dysnatremia (>12 mmol/L/24 hrs or >12 mmol/L/ICU stay). CONCLUSIONS: Dysnatremia was common in surgical ICU patients and was independently associated with an increased risk of in-hospital death in these patients. Dysnatremia at ICU admission was associated with a higher risk of death compared with ICU-acquired dysnatremia. Fluctuations in serum sodium concentrations were independently associated with an increased risk of in-hospital death, even in patients who remained normonatremic during the ICU stay.


Assuntos
Mortalidade Hospitalar , Hipernatremia/epidemiologia , Hiponatremia/epidemiologia , Sódio/sangue , Procedimentos Cirúrgicos Operatórios/mortalidade , Comorbidade , Feminino , Alemanha/epidemiologia , Humanos , Hiperglicemia/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Período Pós-Operatório , Período Pré-Operatório , Prevalência , Estudos Retrospectivos
12.
BMC Ophthalmol ; 13: 74, 2013 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-24304921

RESUMO

BACKGROUND: Health state utility values (HSUVs) are important in the assessment of the cost effectiveness of new interventions. In the case of visual conditions, models generally tend have tended to be built around a set of health states defined by visual acuity (VA). The aim of this review was to assess the impact of VA on HSUVs in patients with diabetic retinopathy, diabetic macular oedema or age-related macular degeneration. METHODS: A systematic literature search was undertaken in major bibliographic databases to identify articles reporting on the relationship between HSUVs and vision. Data were extracted for population characteristics, visual levels and estimated utilities. Evidence from reported statistical models, where available, was considered in the evaluation of vision in the better-seeing eye and the worse-seeing eye. Due to the heterogeneity of included studies, a narrative synthesis was undertaken. RESULTS: Of the 17 relevant studies, 9 studies had data that could be used in the analysis of the impact of vision on HSUVs. Visual loss was associated with a marked impact on health utilities. However, the relationship was not comparable between conditions or by measure of HSUVs. Key results included the finding that overall, self-rated time-trade off estimates were more likely to discriminate between different VA levels than EQ-5D values. Additionally, a stronger correlation was observed between HSUVs and better-seeing eye VA compared to worse-seeing eye VA. CONCLUSIONS: Visual acuity has a significant impact on HSUVs. Nevertheless, care must be taken in the interpretation and use of estimates in cost-effectiveness models due to differences in measures and population diversity.


Assuntos
Retinopatia Diabética , Nível de Saúde , Degeneração Macular , Edema Macular , Retinopatia Diabética/economia , Retinopatia Diabética/terapia , Indicadores Básicos de Saúde , Humanos , Degeneração Macular/economia , Degeneração Macular/terapia , Edema Macular/economia , Edema Macular/terapia , Modelos Econômicos , Modelos Estatísticos , Acuidade Visual
13.
Rev Port Cardiol ; 31(4): 305-8, 2012 Apr.
Artigo em Português | MEDLINE | ID: mdl-22436737

RESUMO

Tricuspid stenosis (TS) is an uncommon complication of transvenous ventricular pacemaker implantation, with few cases reported in the literature. The mechanisms described are obstruction of right ventricular inflow by tricuspid vegetations (endocarditis), multiple pacemaker leads and tricuspid valve (TV) fibrosis secondary to perforation or laceration of the TV leaflets, or adherence between redundant portions of the lead and valvular and subvalvular tissue. We report two cases of severe TS, with different etiologies and management: one caused by leaflet perforation, resolved surgically, and the other secondary to fusion between a loop of the pacemaker lead and the subvalvular apparatus, which was treated medically.


Assuntos
Marca-Passo Artificial/efeitos adversos , Estenose da Valva Tricúspide/etiologia , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Rev Port Cardiol ; 31(2): 167-9, 2012 Feb.
Artigo em Português | MEDLINE | ID: mdl-22222061

RESUMO

Zolmitriptan is a drug used in the acute treatment of migraine, which should not be used in high cardiovascular risk individuals because of its potential to induce vasospasm. We report a rare case of myocardial infarction precipitated by taking zolmitriptan.


Assuntos
Infarto do Miocárdio/induzido quimicamente , Oxazolidinonas/efeitos adversos , Agonistas do Receptor 5-HT1 de Serotonina/efeitos adversos , Triptaminas/efeitos adversos , Idoso , Humanos , Masculino
15.
Rheumatology (Oxford) ; 50(5): 973-81, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21228059

RESUMO

OBJECTIVE: So far, few data are available to characterize the flare history of patients with gout. The objective of this study was to describe the frequency and risk factors of gout flares with special consideration of the comorbidity. METHODS: A cohort study was conducted in a U.K. general practice database (The Health Improvement Network) including all patients aged 20-89 years diagnosed with incident gout between the years 2000 and 2007. RESULTS: In this study, 23 857 incident gout patients (mean age 61.9 years) were included, overall incidence rate was 2.68 (95% CI 2.65, 2.72) per 1000 person-years. The proportion of patients with at least one flare during the follow-up period (mean 3.8 years) was 36.9% (n=8806). A history of ischaemic heart disease [hazard ratio (HR) 1.12 (95% CI 1.06, 1.19)], hypertension [HR 1.15 (95% CI 1.10, 1.20)] and renal failure [HR 1.33 (95% CI 1.20, 1.48)] were independently associated with a higher risk of a first gout flare. Use of allopurinol at initial gout diagnosis was associated with a lower risk [HR 0.80 (95% CI 0.75, 0.85)]. CONCLUSIONS: Gout flares are relatively common among patients with gout. Some of the underlying cardiometabolic comorbid conditions are themselves independent risk factors for flares, which further contribute to the complexity of treatment of gout flares.


Assuntos
Medicina Geral/estatística & dados numéricos , Gota/diagnóstico , Gota/epidemiologia , Índice de Gravidade de Doença , Adulto , Idoso , Idoso de 80 Anos ou mais , Alopurinol/uso terapêutico , Estudos de Coortes , Comorbidade , Feminino , Gota/tratamento farmacológico , Supressores da Gota/uso terapêutico , Humanos , Hipertensão/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Prevalência , Estudos Retrospectivos , Fatores de Risco , Reino Unido/epidemiologia
16.
Semin Respir Crit Care Med ; 32(5): 543-51, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21989690

RESUMO

Multiorgan dysfunction syndrome represents a continuum of cumulative organ dysfunction from very mildly altered function to total and, rarely, irreversible organ failure and is the major cause of death in the intensive care unit (ICU). The terms multiple organ failure syndrome (MOFS), multiple organ system failure (MOSF), and multiple organ failure (MOF) have since been used to describe this syndrome. Infections were initially thought to be the main cause of multiorgan dysfunction; however, other insults, such as severe trauma, burn injuries, and noninfectious inflammatory diseases may precipitate a similar condition. In 2001, several North American and European intensive care societies revisited the definitions for sepsis and related conditions. Additional criteria indicative of physiological derangements were added to the traditional systemic inflammatory response syndrome (SIRS) criteria, including clinical abnormalities (altered mental status, ileus) and biochemical evidence of a sepsis response [procalcitonin (PCT), C-reactive protein (CRP), creatinine, or cytokine levels]. The use of organ failure scores to describe organ dysfunction in ICU patients was encouraged. The pulmonary, cardiovascular, renal, hepatic, hematologic, and central nervous systems are the organs most commonly considered when describing organ dysfunction/failure in the ICU. Scoring systems for organ dysfunction/failure were designed primarily as descriptive tools, aimed at establishing standardized definitions to stratify and compare patients in the ICU in terms of morbidity rather than mortality. Sequential evaluation of organ dysfunction during the ICU stay may track disease progression and may be useful prognostically. We discuss the various scoring systems developed over the past 2 decades and present a rational approach to their role in assessing and following critically ill patients.


Assuntos
Unidades de Terapia Intensiva , Insuficiência de Múltiplos Órgãos/epidemiologia , Sepse/complicações , Proteína C-Reativa/metabolismo , Calcitonina/metabolismo , Peptídeo Relacionado com Gene de Calcitonina , Creatinina/metabolismo , Estado Terminal , Citocinas/metabolismo , Progressão da Doença , Humanos , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/fisiopatologia , Prognóstico , Precursores de Proteínas/metabolismo , Sepse/fisiopatologia
17.
Rev Port Cardiol ; 30(12): 925-7, 2011 Dec.
Artigo em Português | MEDLINE | ID: mdl-22094311

RESUMO

Acute myocardial infarction (AMI) involving acute transmural ischemia of two vascular territories at the same time, which is known as double or combined infarction, is a well described phenomenon but rarely reported in most series of patients admitted for AMI. This may be related to the fact that AMI with multiple vessel obstruction often causes extensive myocardial injury and death before the patient arrives at the hospital. It is speculated that double infarction results from the overall prothrombotic and inflammatory conditions associated with AMI.


Assuntos
Infarto do Miocárdio , Idoso , Humanos , Masculino , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/etiologia , Radiografia
18.
Lancet ; 373(9671): 1253-63, 2009 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-19362675

RESUMO

BACKGROUND: Persistent use of glucocorticoid drugs is associated with bone loss and increased fracture risk. Concurrent oral bisphosphonates increase bone mineral density and reduce frequency of vertebral fractures, but are associated with poor compliance and adherence. We aimed to assess whether one intravenous infusion of zoledronic acid was non-inferior to daily oral risedronate for prevention and treatment of glucocorticoid-induced osteoporosis. METHODS: This 1-year randomised, double-blind, double-dummy, non-inferiority study of 54 centres in 12 European countries, Australia, Hong Kong, Israel, and the USA, tested the effectiveness of 5 mg intravenous infusion of zoledronic acid versus 5 mg oral risedronate for prevention and treatment of glucocorticoid-induced osteoporosis. 833 patients were randomised 1:1 to receive zoledronic acid (n=416) or risedronate (n=417). Patients were stratified by sex, and allocated to prevention or treatment subgroups dependent on duration of glucocorticoid use immediately preceding the study. The treatment subgroup consisted of those treated for more than 3 months (272 patients on zoledronic acid and 273 on risedronate), and the prevention subgroup of those treated for less than 3 months (144 patients on each drug). 62 patients did not complete the study because of adverse events, withdrawal of consent, loss to follow-up, death, misrandomisation, or protocol deviation. The primary endpoint was percentage change from baseline in lumbar spine bone mineral density. Drug efficacy was assessed on a modified intention-to-treat basis and safety was assessed on an intention-to-treat basis. This trial is registered with ClinicalTrials.gov, number NCT00100620. FINDINGS: Zoledronic acid was non-inferior and superior to risedronate for increase of lumbar spine bone mineral density in both the treatment (least-squares mean 4.06% [SE 0.28] vs 2.71% [SE 0.28], mean difference 1.36% [95% CI 0.67-2.05], p=0.0001) and prevention (2.60% [0.45] vs 0.64% [0.46], 1.96% [1.04-2.88], p<0.0001) subgroups at 12 months. Adverse events were more frequent in patients given zoledronic acid than in those on risedronate, largely as a result of transient symptoms during the first 3 days after infusion. Serious adverse events were worsening rheumatoid arthritis for the treatment subgroup and pyrexia for the prevention subgroup. INTERPRETATION: A single 5 mg intravenous infusion of zoledronic acid is non-inferior, possibly more effective, and more acceptable to patients than is 5 mg of oral risedronate daily for prevention and treatment of bone loss that is associated with glucocorticoid use.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Ácido Etidrônico/análogos & derivados , Glucocorticoides/efeitos adversos , Imidazóis/uso terapêutico , Osteoporose , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Densidade Óssea/efeitos dos fármacos , Difosfonatos/efeitos adversos , Método Duplo-Cego , Esquema de Medicação , Ácido Etidrônico/efeitos adversos , Ácido Etidrônico/uso terapêutico , Feminino , Humanos , Imidazóis/efeitos adversos , Infusões Intravenosas , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Osteoporose/induzido quimicamente , Osteoporose/tratamento farmacológico , Ácido Risedrônico , Resultado do Tratamento , Adulto Jovem , Ácido Zoledrônico
19.
Front Plant Sci ; 11: 209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210993

RESUMO

Under natural environment plants experience different light intensities which can affect photosynthesis and consequently the availability of carbohydrates for daytime growth and their transient storage to supply night growth. We grew a spring barley cultivar, Propino, under three different light intensities under warm days and nights, and evaluated the spatial and diurnal adjustments occurring in the transient carbon stores. Leaves under high light at the end of the day accumulated mainly sucrose (30%) and malate (35%), with lower content of hexoses (5%), starch (15%) and fructans (15%). Under low light, plants presented reduced photosynthesis, with lower metabolite contents at end of day. The malate represented 51% of the total carbon accumulated at end of the day, at the expense of sucrose (12%), other metabolite contributions remaining similar to high light. The percentage of metabolites consumed at night was similar for all light intensities with around 75% of the sucrose and starch being mobilized whilst malate and fructans were only partially mobilized with 56 and 44%, respectively. Altogether, sucrose and malate were the main contributors of the total carbon used at night by barley plants, sucrose being predominant under high light (35% vs. 27%), but malate being the major metabolite used under low light with 40% of the total carbon consumed. Interestingly, light intensity also influenced the location of the C transient stores, the plants under low light prioritizing the accumulation of the metabolites, mostly malate, in the youngest tissues. Therefore, light influences quantitatively, but also qualitatively and spatially the carbon stores in the spring barley cv. Propino, suggesting a tight regulation of the primary metabolism.

20.
Food Chem ; 308: 125443, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31654979

RESUMO

Amongst green leafy vegetables, new varieties of lettuce enriched in lutein and ß-carotene are being developed to provide increased supply of dietary carotenoids. We investigated the effect of lettuce genotypes (varieties) and thermal treatments on lutein and ß-carotene bioaccessibility to the micellar fraction (and also carotenoid bioavailability) using a human Caco-2 cell model system. Carotenoid absorption by mammalian cells is not correlated with initial carotenoid concentration in fresh lettuce leaves. While thermal treatment of lettuce leaves increases carotenoid availability, resulting in higher lutein and ß-carotene absorption, disruption of the food matrix by prior cooking results in reduced carotenoid levels and transfer to the micellar fraction. Unless the food matrix is disrupted through breeding or post-harvest treatments, absorption of carotenoids from biofortified lettuce remains similar to lettuce cultivars with low carotenoid levels. Genetic improvement programs for biofortified lettuce varieties need to focus on increasing the carotenoid bioavailability from the food matrix.


Assuntos
Alimentos Fortificados , Lactuca/metabolismo , Luteína/metabolismo , beta Caroteno/metabolismo , Disponibilidade Biológica , Células CACO-2 , Culinária/métodos , Humanos , Verduras/metabolismo
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