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1.
Alzheimers Dement ; 20(4): 2861-2872, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38451782

RESUMO

BACKGROUND: Structural disconnectivity was found to precede dementia. Global white matter abnormalities might also be associated with postoperative delirium (POD). METHODS: We recruited older patients (≥65 years) without dementia that were scheduled for major surgery. Diffusion kurtosis imaging metrics were obtained preoperatively, after 3 and 12 months postoperatively. We calculated fractional anisotropy (FA), mean diffusivity (MD), mean kurtosis (MK), and free water (FW). A structured and validated delirium assessment was performed twice daily. RESULTS: Of 325 patients, 53 patients developed POD (16.3%). Preoperative global MD (standardized beta 0.27 [95% confidence interval [CI] 0.21-0.32] p < 0.001) was higher in patients with POD. Preoperative global MK (-0.07 [95% CI -0.11 to (-0.04)] p < 0.001) and FA (0.07 [95% CI -0.10 to (-0.04)] p < 0.001) were lower. When correcting for baseline diffusion, postoperative MD was lower after 3 months (0.05 [95% CI -0.08 to (-0.03)] p < 0.001; n = 183) and higher after 12 months (0.28 [95% CI 0.20-0.35] p < 0.001; n = 45) among patients with POD. DISCUSSION: Preoperative structural disconnectivity was associated with POD. POD might lead to white matter depletion 3 and 12 months after surgery.


Assuntos
Demência , Delírio do Despertar , Substância Branca , Humanos , Idoso , Estudos de Coortes , Substância Branca/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos
2.
Brain ; 145(6): 2064-2076, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35377407

RESUMO

There is substantial interest in the potential for traumatic brain injury to result in progressive neurological deterioration. While blood biomarkers such as glial fibrillary acid protein (GFAP) and neurofilament light have been widely explored in characterizing acute traumatic brain injury (TBI), their use in the chronic phase is limited. Given increasing evidence that these proteins may be markers of ongoing neurodegeneration in a range of diseases, we examined their relationship to imaging changes and functional outcome in the months to years following TBI. Two-hundred and three patients were recruited in two separate cohorts; 6 months post-injury (n = 165); and >5 years post-injury (n = 38; 12 of whom also provided data ∼8 months post-TBI). Subjects underwent blood biomarker sampling (n = 199) and MRI (n = 172; including diffusion tensor imaging). Data from patient cohorts were compared to 59 healthy volunteers and 21 non-brain injury trauma controls. Mean diffusivity and fractional anisotropy were calculated in cortical grey matter, deep grey matter and whole brain white matter. Accelerated brain ageing was calculated at a whole brain level as the predicted age difference defined using T1-weighted images, and at a voxel-based level as the annualized Jacobian determinants in white matter and grey matter, referenced to a population of 652 healthy control subjects. Serum neurofilament light concentrations were elevated in the early chronic phase. While GFAP values were within the normal range at ∼8 months, many patients showed a secondary and temporally distinct elevations up to >5 years after injury. Biomarker elevation at 6 months was significantly related to metrics of microstructural injury on diffusion tensor imaging. Biomarker levels at ∼8 months predicted white matter volume loss at >5 years, and annualized brain volume loss between ∼8 months and 5 years. Patients who worsened functionally between ∼8 months and >5 years showed higher than predicted brain age and elevated neurofilament light levels. GFAP and neurofilament light levels can remain elevated months to years after TBI, and show distinct temporal profiles. These elevations correlate closely with microstructural injury in both grey and white matter on contemporaneous quantitative diffusion tensor imaging. Neurofilament light elevations at ∼8 months may predict ongoing white matter and brain volume loss over >5 years of follow-up. If confirmed, these findings suggest that blood biomarker levels at late time points could be used to identify TBI survivors who are at high risk of progressive neurological damage.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Substância Branca , Biomarcadores , Lesões Encefálicas/complicações , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Progressão da Doença , Proteína Glial Fibrilar Ácida/metabolismo , Humanos
3.
Mol Psychiatry ; 26(12): 7346-7354, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34535766

RESUMO

Inflammation is associated with depressive symptoms and innate immune mechanisms are likely causal in some cases of major depression. Systemic inflammation also perturbs brain function and microstructure, though how these are related remains unclear. We recruited N = 46 healthy controls, and N = 83 depressed cases stratified by CRP (> 3 mg/L: N = 33; < 3 mg/L: N = 50). All completed clinical assessment, venous blood sampling for C-reactive protein (CRP) assay, and brain magnetic resonance imaging (MRI). Micro-structural MRI parameters including proton density (PD), a measure of tissue water content, were measured at 360 cortical and 16 subcortical regions. Resting-state fMRI time series were correlated to estimate functional connectivity between individual regions, as well as the sum of connectivity (weighted degree) of each region. Multiple tests for regional analysis were controlled by the false discovery rate (FDR = 5%). We found that CRP was significantly associated with PD in precuneus, posterior cingulate cortex (pC/pCC) and medial prefrontal cortex (mPFC); and with functional connectivity between pC/pCC, mPFC and hippocampus. Depression was associated with reduced weighted degree of pC/pCC, mPFC, and other nodes of the default mode network (DMN). Thus CRP-related increases in proton density-a plausible marker of extracellular oedema-and changes in functional connectivity were anatomically co-localised with DMN nodes that also demonstrated significantly reduced hubness in depression. We suggest that effects of peripheral inflammation on DMN node micro-structure and connectivity may mediate inflammatory effects on depression.


Assuntos
Encéfalo , Depressão , Mapeamento Encefálico , Humanos , Inflamação , Imageamento por Ressonância Magnética/métodos , Vias Neurais
4.
Brain ; 144(11): 3492-3504, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34240124

RESUMO

Metabolic derangements following traumatic brain injury are poorly characterized. In this single-centre observational cohort study we combined 18F-FDG and multi-tracer oxygen-15 PET to comprehensively characterize the extent and spatial pattern of metabolic derangements. Twenty-six patients requiring sedation and ventilation with intracranial pressure monitoring following head injury within a Neurosciences Critical Care Unit, and 47 healthy volunteers were recruited. Eighteen volunteers were excluded for age over 60 years (n = 11), movement-related artefact (n = 3) or physiological instability during imaging (n = 4). We measured cerebral blood flow, blood volume, oxygen extraction fraction, and 18F-FDG transport into the brain (K1) and its phosphorylation (k3). We calculated oxygen metabolism, 18F-FDG influx rate constant (Ki), glucose metabolism and the oxygen/glucose metabolic ratio. Lesion core, penumbra and peri-penumbra, and normal-appearing brain, ischaemic brain volume and k3 hotspot regions were compared with plasma and microdialysis glucose in patients. Twenty-six head injury patients, median age 40 years (22 male, four female) underwent 34 combined 18F-FDG and oxygen-15 PET at early, intermediate, and late time points (within 24 h, Days 2-5, and Days 6-12 post-injury; n = 12, 8, and 14, respectively), and were compared with 20 volunteers, median age 43 years (15 male, five female) who underwent oxygen-15, and nine volunteers, median age 56 years (three male, six female) who underwent 18F-FDG PET. Higher plasma glucose was associated with higher microdialysate glucose. Blood flow and K1 were decreased in the vicinity of lesions, and closely related when blood flow was <25 ml/100 ml/min. Within normal-appearing brain, K1 was maintained despite lower blood flow than volunteers. Glucose utilization was globally reduced in comparison with volunteers (P < 0.001). k3 was variable; highest within lesions with some patients showing increases with blood flow <25 ml/100 ml/min, but falling steeply with blood flow lower than 12 ml/100 ml/min. k3 hotspots were found distant from lesions, with k3 increases associated with lower plasma glucose (Rho -0.33, P < 0.001) and microdialysis glucose (Rho -0.73, P = 0.02). k3 hotspots showed similar K1 and glucose metabolism to volunteers despite lower blood flow and oxygen metabolism (P < 0.001, both comparisons); oxygen extraction fraction increases consistent with ischaemia were uncommon. We show that glucose delivery was dependent on plasma glucose and cerebral blood flow. Overall glucose utilization was low, but regional increases were associated with reductions in glucose availability, blood flow and oxygen metabolism in the absence of ischaemia. Clinical management should optimize blood flow and glucose delivery and could explore the use of alternative energy substrates.


Assuntos
Lesões Encefálicas Traumáticas/metabolismo , Circulação Cerebrovascular/fisiologia , Glucose/metabolismo , Adulto , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons
5.
Neuroimage ; 210: 116542, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31958583

RESUMO

Ultra-high field functional magnetic resonance imaging (fMRI) has allowed us to acquire images with submillimetre voxels. However, in order to interpret the data clearly, we need to accurately correct head motion and the resultant distortions. Here, we present a novel application of Boundary Based Registration (BBR) to realign functional Magnetic Resonance Imaging (fMRI) data and evaluate its effectiveness on a set of 7T submillimetre data, as well as millimetre 3T data for comparison. BBR utilizes the boundary information from high contrast present in structural data to drive registration of functional data to the structural data. In our application, we realign each functional volume individually to the structural data, effectively realigning them to each other. In addition, this realignment method removes the need for a secondary aligning of functional data to structural data for purposes such as laminar segmentation or registration to data from other scanners. We demonstrate that BBR realignment outperforms standard realignment methods across a variety of data analysis methods. For instance, the method results in a 15% increase in linear discriminant contrast, a cross-validated estimate of multivariate discriminability. Further analysis shows that this benefit is an inherent property of the BBR cost function and not due to the difference in target volume. Our results show that BBR realignment is able to accurately correct head motion in 7T data and can be utilized in preprocessing pipelines to improve the quality of 7T data.


Assuntos
Mapeamento Encefálico/normas , Córtex Cerebral/fisiologia , Movimentos da Cabeça , Processamento de Imagem Assistida por Computador/normas , Imageamento por Ressonância Magnética/normas , Reconhecimento Visual de Modelos/fisiologia , Adulto , Atenção/fisiologia , Mapeamento Encefálico/métodos , Córtex Cerebral/diagnóstico por imagem , Reconhecimento Facial/fisiologia , Fixação Ocular/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Percepção Espacial/fisiologia
6.
New Phytol ; 222(2): 1054-1060, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30372538

RESUMO

Seed dispersal allows plants to colonise new sites and escape from pathogens and intraspecific competition, maintaining plant genetic diversity and regulating plant distribution. Conversely, most plant species form mutualistic associations with arbuscular mycorrhizal (AM) fungi in a symbiosis established immediately after seed germination. Because AM fungi are obligate symbionts, using the same dispersal vector as their host should be highly advantageous for their survival, but the co-dispersal of seeds and AM fungal spores has never been confirmed. We aim to clarify the potential role of European birds, essential dispersers for many plant species, as co-dispersers of seeds and AM fungal spores. In total, 63 bird droppings with intact seeds were placed in sterilised soil and maintained for 4 months in a protected environment to avoid contamination. Additionally, 173 bird droppings and 729 gauze swabs used to clean birds' feet were inspected for AM fungal spores. Although no spores were detected by direct observation of these samples, seven Rubus ulmifolius seedlings obtained from four independent droppings of Erithacus rubecula and Sylvia melanocephala were colonised by AM fungi. Our results show that birds can effectively co-disperse viable seeds and AM fungal spores, potentially over long distances, providing a pivotal mechanism to understand the cosmopolitan distribution of AM fungi.


Assuntos
Aves/fisiologia , Micorrizas/fisiologia , Plantas/metabolismo , Dispersão de Sementes/fisiologia , Animais , Rubus/microbiologia , Esporos Fúngicos/fisiologia
7.
Biol Lett ; 15(5): 20180770, 2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-31039725

RESUMO

Mutualistic interactions like those established between plants and mycorrhizal fungi or seed dispersers are key drivers of plant population dynamics and ecosystem functioning; however, these interactions have rarely been explored together. We assembled a tripartite fungi-plant-disperser network in the Gorongosa National Park-Mozambique, to test (1) if diversity and importance of plant mutualists above- and belowground are correlated, and (2) whether biotically and abiotically dispersed plants are associated with distinct arbuscular mycorrhizal fungi (AMF). We quantified seed dispersal by animals for 1 year and characterized the AMF of 26 common plant species. Sixteen plant species were dispersed by 15 animals and colonized by 48 AMF virtual taxa (VT), while the remaining 10 plant species were not dispersed by animals and associated with 34 AMF VT. We found no evidence for a correlation between the number of plant partners above- and belowground or on plant specialization on both types of partners. We also found no evidence for differentiation of AMF communities between biotically and abiotically dispersed plants. Our results suggest that the establishment of plant interactions with seed dispersers and mycorrhizal fungi is largely independent and that both biotically and abiotically dispersed plants seem to associate with similar communities of AMF.


Assuntos
Micorrizas , Dispersão de Sementes , Animais , Ecossistema , Moçambique , Raízes de Plantas , Sementes
8.
Ecol Lett ; 21(5): 683-691, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29536599

RESUMO

Seed dispersal and mycorrhizal associations are key mutualisms for the functioning and regeneration of plant communities; however, these processes have seldom been explored together. We hypothesised that obligatory mycorrhizal plants will be less likely to have long-distance dispersal (LDD) syndromes since the probability of finding suitable mycorrhizal partners is likely to decrease with distance to the mother plant. We contrasted the mycorrhizal status and LDD syndromes for 1960 European plant species, using phylogenetically corrected log-linear models. Contrary to our expectation, having specialised structures for LDD is more frequent in obligate mycorrhizal plants than in non-mycorrhizal plants, revealing that lack of compatible mutualists does not constrain investment in LDD structures in the European Flora. Ectomycorrhizal plants associated with wind-dispersing fungi are also more likely to have specialised structures for wind dispersal. Habitat specificity and narrower niche of non-mycorrhizal plants might explain the smaller investment in specialised structures for seed dispersal.


Assuntos
Micorrizas , Dispersão de Sementes , Plantas , Sementes , Simbiose
9.
Hum Brain Mapp ; 39(10): 4018-4031, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29885014

RESUMO

We evaluated the effectiveness of prospective motion correction (PMC) on a simple visual task when no deliberate subject motion was present. The PMC system utilizes an in-bore optical camera to track an external marker attached to the participant via a custom-molded mouthpiece. The study was conducted at two resolutions (1.5 mm vs 3 mm) and under three conditions (PMC On and Mouthpiece On vs PMC Off and Mouthpiece On vs PMC Off and Mouthpiece Off). Multiple data analysis methods were conducted, including univariate and multivariate approaches, and we demonstrated that the benefit of PMC is most apparent for multi-voxel pattern decoding at higher resolutions. Additional testing on two participants showed that our inexpensive, commercially available mouthpiece solution produced comparable results to a dentist-molded mouthpiece. Our results showed that PMC is increasingly important at higher resolutions for analyses that require accurate voxel registration across time.


Assuntos
Artefatos , Neuroimagem Funcional/normas , Movimentos da Cabeça , Processamento de Imagem Assistida por Computador/normas , Imageamento por Ressonância Magnética/normas , Reconhecimento Automatizado de Padrão/normas , Reconhecimento Visual de Modelos/fisiologia , Máquina de Vetores de Suporte , Córtex Visual/fisiologia , Adulto , Neuroimagem Funcional/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Reconhecimento Automatizado de Padrão/métodos , Sensibilidade e Especificidade , Córtex Visual/diagnóstico por imagem
10.
New Phytol ; 213(1): 380-390, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27560189

RESUMO

Understanding the distribution and diversity of arbuscular mycorrhizal fungi (AMF) and the rules that govern AMF assemblages has been hampered by a lack of data from natural ecosystems. In addition, the current knowledge on AMF diversity is biased towards temperate ecosystems, whereas little is known about other habitats such as dry tropical ecosystems. We explored the diversity and structure of AMF communities in grasslands, savannas, dry forests and miombo in a protected area under dry tropical climate (Gorongosa National Park, Mozambique) using 454 pyrosequencing. In total, 147 AMF virtual taxa (VT) were detected, including 22 VT new to science. We found a high turnover of AMF with ˂ 12% of VT present in all vegetation types. Forested areas supported more diverse AMF communities than savannas and grassland. Miombo woodlands had the highest AMF richness, number of novel VT, and number of exclusive and indicator taxa. Our data reveal a sharp differentiation of AMF communities between forested areas and periodically flooded savannas and grasslands. This marked ecological structure of AMF communities provides the first comprehensive landscape-scale evidence that, at the background of globally low endemism of AMF, local communities are shaped by regional processes including environmental filtering by edaphic properties and natural disturbance.


Assuntos
Ecossistema , Glomeromycota/fisiologia , Micorrizas/fisiologia , Clima Tropical , África , Biodiversidade , Solo/química
11.
Conserv Biol ; 31(1): 76-85, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27355794

RESUMO

Large animals are important seed dispersers; however, they tend to be under a high extinction risk worldwide. There is compelling evidence that the global biodiversity crisis is leading to the deterioration of several ecosystem functions, but there is virtually no information on how large-scale refaunation efforts can reinstate seed dispersal. We evaluated the effectiveness of a 62-km2 wildlife sanctuary, which was established to recover populations of large mammals in Gorongosa National Park (Mozambique), in restoring seed dispersal. We collected animal scats during the dry season of 2014 (June-August) along 5 transects inside and 5 transects outside the sanctuary fence (50 km total) with the same type of plant community, identified animal and plant species in the transects, and quantified the number of seeds in each scat. Based on these data, we built bipartite networks and calculated network and species-level descriptor values, and we compared data collected inside and outside the sanctuary. There were more scats (268 vs. 207) and more scats containing seeds (132 vs. 94) inside than outside the sanctuary. The number of mammal dispersers was also higher inside (17) than outside the sanctuary (11). Similarly, more seeds (2413 vs. 2124) and plant species (33 vs. 26) were dispersed inside than outside the sanctuary. Overall, the seed-dispersal network was less specialized (0.38 vs. 0.44) and there was a greater overlap (0.16 vs. 0.07) inside than outside the sanctuary. Both networks were significantly modular and antinested. The high number and richness of seeds dispersed inside the sanctuary was explained mostly by a higher abundance of dispersers rather than by disperser identity. Our results suggest conservation efforts aimed at recovering populations of large mammals are helping to reestablish not only target mammal species but also their functional roles as seed dispersers in the ecosystem.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Dispersão de Sementes , Animais , Mamíferos , Moçambique , Parques Recreativos , Sementes
12.
Neuroimage ; 111: 85-99, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25676915

RESUMO

Diffusion kurtosis imaging (DKI) is a diffusion-weighted technique which overcomes limitations of the commonly used diffusion tensor imaging approach. This technique models non-Gaussian behaviour of water diffusion by the diffusion kurtosis tensor (KT), which can be used to provide indices of tissue heterogeneity and a better characterisation of the spatial architecture of tissue microstructure. In this study, the geometry of the KT is elucidated using synthetic data generated from multi-compartmental models, where diffusion heterogeneity between intra- and extra-cellular media is taken into account, as well as the sensitivity of the results to each model parameter and to synthetic noise. Furthermore, based on the assumption that the maxima of the KT are distributed perpendicularly to the direction of well-aligned fibres, a novel algorithm for estimating fibre direction directly from the KT is proposed and compared to the fibre directions extracted from DKI-based orientation distribution function (ODF) estimates previously proposed in the literature. Synthetic data results showed that, for fibres crossing at high intersection angles, direction estimates extracted directly from the KT have smaller errors than the DKI-based ODF estimation approaches (DKI-ODF). Nevertheless, the proposed method showed smaller angular resolution and lower stability to changes of the simulation parameters. On real data, tractography performed on these KT fibre estimates suggests a higher sensitivity than the DKI-based ODF in resolving lateral corpus callosum fibres reaching the pre-central cortex when diffusion acquisition is performed with five b-values. Using faster acquisition schemes, KT-based tractography did not show improved performance over the DKI-ODF procedures. Nevertheless, it is shown that direct KT fibre estimates are more adequate for computing a generalised version of radial kurtosis maps.


Assuntos
Encéfalo/anatomia & histologia , Imagem de Difusão por Ressonância Magnética/métodos , Fibras Nervosas Mielinizadas , Adulto , Biomarcadores , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino
13.
Int J Med Microbiol ; 304(3-4): 314-20, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24447914

RESUMO

Helicobacter pylori colonizes half of the world population and is associated with gastric cancer. We have previously demonstrated that docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid known for its anti-inflammatory and antitumor effects, directly inhibits H. pylori growth in vitro and in mice. Nevertheless, the concentration of DHA shown to reduce H. pylori mice gastric colonization was ineffective in vitro. Related to the auxotrophy of H. pylori for cholesterol, we hypothesize that other mechanisms, in addition to DHA direct antibacterial effect, must be responsible for the reduction of the infection burden. In the present study we investigated if DHA affects also H. pylori growth, by reducing the availability of membrane cholesterol in the epithelial cell for H. pylori uptake. Levels of cholesterol in gastric epithelial cells and of cholesteryl glucosides in H. pylori were determined by thin layer chromatography and gas chromatography. The consequences of epithelial cells' cholesterol depletion on H. pylori growth were assessed in liquid cultures. We show that H. pylori uptakes cholesterol from epithelial cells. In addition, DHA lowers cholesterol levels in epithelial cells, decreases its de novo synthesis, leading to a lower synthesis of cholesteryl glucosides by H. pylori. A previous exposition of H. pylori to cholesterol influences the bacterium response to the direct inhibitory effect of DHA. Overall, our results suggest that a direct effect of DHA on H. pylori survival is modulated by its access to epithelial cell cholesterol, supporting the notion that cholesterol enhances the resistance of H. pylori. The cholesterol-dependent resistance of H. pylori to antimicrobial compounds raises new important aspects for the development of new anti-bacterial strategies.


Assuntos
Antibacterianos/metabolismo , Colesterol/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Farmacorresistência Bacteriana , Células Epiteliais/microbiologia , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/metabolismo , Linhagem Celular , Cromatografia em Camada Fina , Células Epiteliais/química , Cromatografia Gasosa-Espectrometria de Massas , Helicobacter pylori/química , Helicobacter pylori/crescimento & desenvolvimento , Humanos
14.
Artigo em Inglês | MEDLINE | ID: mdl-38541272

RESUMO

BACKGROUND: The main objective of the present study was to assess e-health literacy in a sample of Portuguese university students and its association with the level of knowledge and seeking for COVID-19-related information. METHODS: This cross-sectional online study was conducted on Portuguese university students. All students completed a questionnaire consisting of demographic characteristics, e-health Literacy Scale (eHEALS), and a questionnaire about knowledge, attitude, and health online information seeking. RESULTS: A total of 534 students (76.8% women), with a mean age of 24.3 years old (SD = 7.8), participated in this cross-sectional study, 53.0% of students were from non-health sciences. The mean score of eHEALS literacy was 28.8 (SD = 5.6). Most students (71.1%) classified the Internet as a useful, or very useful, tool in helping them make health related decisions. The use of the Internet as a tool to research health information for a period of two or more hours (OR = 1.9; CI 95% = 1.2; 3.4), to search online for health information on professional websites (OR = 2.3; CI 95% = 1.4; 3.6), to search in official media (OR = 2.3; CI 95% = 1.4; 3.9), and to study in the field of health sciences (OR = 1.6; CI 95% = 1.1; 2.6) increased the likelihood of having sufficient e-health literacy. CONCLUSION: From a public health perspective, there is a need to develop programs that increase health literacy among university students.


Assuntos
Letramento em Saúde , Telemedicina , Humanos , Feminino , Adulto Jovem , Adulto , Masculino , Estudos Transversais , Universidades , Portugal , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , Estudantes , Internet
15.
Br J Nutr ; 109(2): 322-8, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-22717003

RESUMO

Nutritional evaluation may predict clinical outcomes, such as hospital length of stay (LOS). We aimed to assess the value of nutritional risk and status methods, and to test standard anthropometry percentiles v. the 50th percentile threshold in predicting LOS, and to determine nutritional status changes during hospitalisation and their relation with LOS. In this longitudinal prospective study, 298 surgical patients were evaluated at admission and discharge. At admission, nutritional risk was assessed by Nutritional Risk Screening-2002 (NRS-2002), Malnutrition Universal Screening Tool (MUST) and nutritional status by Subjective Global Assessment (SGA), involuntary % weight loss in the previous 6 months and anthropometric parameters; % weight loss and anthropometry were reassessed at discharge. At admission, risk/undernutrition results by NRS-2002 (P< 0.001), MUST (P< 0.001), % weight loss (P< 0.001) and SGA (P< 0.001) were predictive of longer LOS. A mid-arm circumference (MAC) or a mid-arm muscle circumference (MAMA) under the 15th and the 50th percentile, which was considered indicative of undernutrition, did predict longer LOS (P< 0.001); conversely, there was no association between depleted triceps skinfold (TSF) and longer LOS. In-hospital, there was a high prevalence of weight, muscle and fat losses, associated with longer LOS. At discharge, patients with a simultaneous negative variation in TSF+MAC+MAMA (n 158, 53 %) had longer LOS than patients with a TSF+MAC+MAMA positive variation (11 (8-15) v. 8 (7-12) d, P< 0.001). We concluded that at risk or undernutrition evaluated by all methods, except TSF and BMI, predicted a longer LOS. Moreover, MAC and MAMA measurements and their classification according to the 50th percentile threshold seem reliable undernutrition indicators.


Assuntos
Desnutrição/epidemiologia , Estado Nutricional , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Hospitais Universitários , Hospitais Urbanos , Humanos , Tempo de Internação , Estudos Longitudinais , Masculino , Desnutrição/complicações , Pessoa de Meia-Idade , Avaliação Nutricional , Portugal/epidemiologia , Valor Preditivo dos Testes , Prevalência , Estudos Prospectivos , Centro Cirúrgico Hospitalar , Adulto Jovem
16.
Artigo em Inglês | MEDLINE | ID: mdl-36767871

RESUMO

Previous research has already shown the negative impact of the COVID-19 pandemic on college students' well-being and mental health. Eating problems and weight gain due to changes in eating habits and physical activity experienced during this period have also been noticed. However, few studies have explored the role of students' resources as used during the COVID-19 pandemic, such as coping strategies. This study aimed to (1) explore the associations among psychological distress, disordered eating, coping strategies, and weight changes; (2) examine the moderating role of coping strategies in the process of weight gain and weight loss; and (3) study the mediating role of coping strategies in the process of weight gain and weight loss. The participants in this study were 772 students at a Portuguese university. The data collected included sociodemographic data and three self-reported questionnaires (Depression, Anxiety, and Stress Scale; Eating Disorder Examination Questionnaire; Brief COPE) during the first few months of the pandemic, which included a 72-day full national lockdown. The results showed that depression, anxiety, stress, and disordered eating were related to increased weight. Guilt, denial, self-distraction, use of substances, and behavior disinvestment were also related to increased weight. Behavioral disinvestment had a strong mediating effect on weight gain. Additionally, planning, positive reframing, and acceptance all showed a moderating effect between psychological distress and weight changes. In conclusion, coping strategies allow for a better understanding of the mechanisms by which psychological distress and disordered eating were related to weight changes during the pandemic.


Assuntos
COVID-19 , Transtornos da Alimentação e da Ingestão de Alimentos , Angústia Psicológica , Humanos , Pandemias , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Adaptação Psicológica , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Redução de Peso , Aumento de Peso , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia
17.
Nutrients ; 15(16)2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37630815

RESUMO

The Mediterranean diet is a healthy dietary pattern whose main characteristic is olive oil consumption. The potential health benefits of olive oil have been extensively investigated and the present review provides the more recent clinical evidence supporting the positive impact of olive oil intake on human health. PubMed (n = 227) and Scopus (n = 308) databases were searched for published clinical studies in English over the past six years (October 2016 to December 2022), following key word searches of "olive oil" and "health". Major findings associated olive oil with antioxidant and anti-inflammatory effects, improvement in endothelial function and lipid profile, prevention of obesity, diabetes, cardiovascular and neurodegenerative diseases, and modulation of the gut microbiota. These benefits are attributed to the nutritional composition of olive oil, which has a high content of monounsaturated fatty acids (MUFA) (oleic acid in particular) and minor compounds such as polyphenols (oleuropein and hydroxytyrosol). Although additional research continues to be required, the more recently generated evidence supports the potential of olive oil to contribute beneficially to health and to the prevention and management of a variety of non-communicable diseases, as a consequence of the synergism between its components' complexity.


Assuntos
Dieta Mediterrânea , Microbioma Gastrointestinal , Humanos , Antioxidantes , Bases de Dados Factuais , Ácidos Graxos Monoinsaturados , Azeite de Oliva
18.
Nutrients ; 15(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37571288

RESUMO

(1) Background: Extra virgin olive oil (EVOO) is studied mostly for its health benefits in preventing non-communicable chronic diseases, particularly within a Mediterranean dietary pattern. However, few studies have addressed the effect of EVOO in healthy individuals, prior to an established disease. This study aims to evaluate the impact of Northern Portuguese polyphenol-rich EVOO (NPPR-EVOO) consumption on various important clinical parameters in healthy adult volunteers. (2) Methods: This quasi-experimental intervention study assessed the impact of NPPR-EVOO for a period of 100 days. Serum total cholesterol, HbA1c, HDL-c, LDL-c, and CRP, and anthropometric measures-waist and hip perimeters, hand grip strength, and body fat-were assessed and food logs were analyzed. (3) Results: Serum HbA1c (5.12 ± 0.32%; 4.93 ± 0.24, p = 0.000) and LDL-c (96.50 ± 28.57 mg/dL; 87.41 ± 31.38 mg/dL, p = 0.017) significantly decreased following NPPR-EVOO. Also, daily energy significantly increased, but no changes in other dietary parameters, or anthropometry, were seen. Adherence to the Mediterranean diet did not explain the differences found in individuals regarding serum lipid profile and HbA1c, reinforcing the role of EVOO's effect. (4) Conclusions: NPPR-EVOO lowered the serum levels of LDL cholesterol and HbA1c, providing clues on the effect of EVOO-putative health benefits. These results pave the way for a deeper exploration of EVOO as a functional food.


Assuntos
Força da Mão , Adulto , Humanos , Azeite de Oliva , LDL-Colesterol , Voluntários Saudáveis , Hemoglobinas Glicadas , Portugal
19.
Nutrients ; 15(10)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37242125

RESUMO

(1) Background: Gastric cancer patients are known to be at a high risk of malnutrition, sarcopenia, and cachexia, and the latter impairs the patient's nutritional status during their clinical course and also treatment response. A clearer identification of nutrition-related critical points during neoadjuvant treatment for gastric cancer is relevant to managing patient care and predicting clinical outcomes. The aim of this systematic review was to identify and describe nutrition-related critical domains associated with clinical outcomes. (2) Methods: We performed a systematic review (PROSPERO ID:CRD42021266760); (3) Results: This review included 14 studies compiled into three critical domains: patient-related, clinical-related (disease and treatment), and healthcare-related. Body composition changes during neoadjuvant chemotherapy (NAC) accounted for the early termination of chemotherapy and reduced overall survival. Sarcopenia was confirmed to have an independent prognostic value. The role of nutritional interventions during NAC has not been fully explored. (4) Conclusions: Understanding critical domain exposures affecting nutritional status will enable better clinical approaches to optimize care plans. It may also provide an opportunity for the mitigation of poor nutritional status and sarcopenia and their deleterious clinical consequences.


Assuntos
Desnutrição , Sarcopenia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamento farmacológico , Terapia Neoadjuvante , Procedimentos Clínicos , Sarcopenia/etiologia , Estado Nutricional
20.
PLoS One ; 18(5): e0285317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37141328

RESUMO

Throughout the pandemic of COVID-19 caused by SARS-CoV-2, university students were considered a vulnerable risk group for mental health impairment and wellbeing deterioration. This study aimed at evaluating the pandemic's impact on the physical and mental health and wellbeing among students of a Portuguese university. This cross-sectional study included 913 participants and ran from June to October 2020. Data collected included sociodemographics, three mental health self-report questionnaires (Depression Anxiety Stress Scale, Eating Disorder Examination Questionnaire and Brief COPE) and lifestyle practices (eating and sleeping patterns, media, and entertainment habits) during the first months of the pandemic, which included a 72-day full national lockdown. Descriptive and correlational statistical analysis were conducted. Students' food habits changed during the pandemic, namely on the consumption of snacks and fast food and, overall, less balanced meals became more prevalent. Additionally, almost 70% of the students reported Body Mass Index changes, while 59% went through sleep pattern changes-these were more pronounced in women and younger students. Over half (67%) of the inquirees exhibited an increase in their stress, depression, and generalized anxiety symptoms. Also, the study demonstrates that students' lifestyles trended negatively during the pandemic and highlights how important regular psychological, health monitoring and emotional support is, amongst this somehow overlooked population throughout the pandemic. Universities should provide support to overcome challenges in future stressful situations. This study might have an impact on how universities and higher education systems approach their students in terms of mental and physical health monitoring and promotion in future situations, non-related with COVID. Moreover, it has a large sample of students well characterized in terms of mental and physical health, which might be of interest for future comparison with other worldwide group of students throughout stressful situations, such as tragic events, wars, pandemics.


Assuntos
COVID-19 , Humanos , Feminino , COVID-19/epidemiologia , COVID-19/psicologia , Pandemias , Portugal/epidemiologia , SARS-CoV-2 , Estudos Transversais , Universidades , Depressão/epidemiologia , Estresse Psicológico/psicologia , Controle de Doenças Transmissíveis , Ansiedade/psicologia , Estudantes/psicologia
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