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1.
BMC Health Serv Res ; 24(1): 645, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769571

RESUMO

BACKGROUND: Social prescribing (SP) is a non-clinical approach, most commonly based in healthcare units, that aims to address non-medical health-related social needs by connecting individuals with community-based services. This qualitative study explores the perception of Portuguese older adults regarding the benefits of SP and their willingness to participate in SP initiatives. METHODS: Three face-to-face focus group sessions were conducted with 23 participants in different cities in Portugal. Open and semi-open questions were used to guide the discussions and thematic analysis was used to analyze the data. RESULTS: The participants recognized the potential benefits of SP for older adults, including diversifying leisure activities, improving mental health, and complementing existing support systems. They highlighted the need for external support, usually in the form of link workers, to facilitate personalized referrals and consider individual characteristics and preferences. While some participants expressed reluctance to engage in SP due to their existing busy schedules and a perceived sense of imposition, others showed openness to having new experiences and recognized the potential value of SP in promoting activity. Barriers to participation, including resistance to change, mobility issues, and family responsibilities, were identified. CONCLUSIONS: The study emphasizes the importance of a person-centered and co-designed approach to SP, involving older adults in the planning and implementation of interventions. The findings provide valuable insights for the development of SP programs tailored to the unique needs and aspirations of older adults in Portugal, ultimately promoting active and healthy aging. Future research should consider the perspectives of family doctors and include a broader representation of older adults from diverse geographic areas.


Assuntos
Grupos Focais , Pesquisa Qualitativa , Humanos , Portugal , Masculino , Idoso , Feminino , Idoso de 80 Anos ou mais , Apoio Social , Pessoa de Meia-Idade
2.
Biomimetics (Basel) ; 9(3)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38534820

RESUMO

Atherosclerosis represents the etiologic source of several cardiovascular events, including myocardial infarction, cerebrovascular accidents, and peripheral artery disease, which remain the leading cause of mortality in the world. Numerous strategies are being delineated to revert the non-optimal projections of the World Health Organization, by both designing new diagnostic and therapeutic approaches or improving the interventional procedures performed by physicians. Deeply understanding the pathological process of atherosclerosis is, therefore, mandatory to accomplish improved results in these trials. Due to their availability, reproducibility, low expensiveness, and rapid production, biomimicking physical models are preferred over animal experimentation because they can overcome some limitations, mainly related to replicability and ethical issues. Their capability to represent any atherosclerotic stage and/or plaque type makes them valuable tools to investigate hemodynamical, pharmacodynamical, and biomechanical behaviors, as well as to optimize imaging systems and, thus, obtain meaningful prospects to improve the efficacy and effectiveness of treatment on a patient-specific basis. However, the broadness of possible applications in which these biomodels can be used is associated with a wide range of tissue-mimicking materials that are selected depending on the final purpose of the model and, consequently, prioritizing some materials' properties over others. This review aims to summarize the progress in fabricating biomimicking atherosclerotic models, mainly focusing on using materials according to the intended application.

3.
Prev Med Rep ; 39: 102652, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38384966

RESUMO

Background: In order to address health inequalities, which have been exacerbated by the COVID-19 pandemic, and promote older adults' quality of life, it is necessary to explore non-medical approaches such as social prescribing. Social prescribing is a person-centered approach that allows health professionals to refer patients to services provided by the social and community sectors. This study aimed to explore older adults' perceptions of social prescribing in mainland Portugal and to identify factors associated with these perceptions, providing insights for future implementation strategies. Methods: A cross-sectional study was conducted with 613 older adults aged 65 to 93. Participants' sociodemographic, economic, and health characteristics were assessed, along with their perceptions of social prescribing's benefits and activity interest. Results: Over 75% of respondents agreed that social prescribing would benefit the health system and their community. Most participants (87.7% and 89.7%, respectively) thought that activities like personal protection and development activities and cultural enrichment would be particularly relevant to them. Factors such as marital status, education, health status, and pain/discomfort levels influenced the perceived relevance of these activities. Conclusion: This study reveals that older adults in mainland Portugal are open to social prescribing and suggests that tailored interventions considering individual preferences and characteristics can lead to more effective implementation and equal access to social prescribing. Further research and policy efforts should focus on integrating social prescribing into the healthcare system to support healthy aging in Portugal.

4.
Front Public Health ; 11: 1149731, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37124788

RESUMO

Objective: This study aims to assess the active aging awareness of older adults in mainland Portugal and their levels of overall well-being and to identify social and health-related factors. Methods: A cross-sectional study was conducted with a representative sample of 613 older adults, aged 65 or older, who participated in the PROKnos - Knowing Social Prescribing needs of the elderly study in Portugal. The questionnaire consisted of the Active Ageing Awareness Questionnaire and the World Health Organization - Five Well-Being Index, as well as sociodemographic, economic, and health status questions. Correlation coefficients, t-tests for independent samples, and one-way ANOVA were used to explore potential associations between variables. Results: The active aging awareness levels were significantly higher for women (p = 0.031), and those who were younger (p = 0.011), more educated (p < 0.001), had a better financial situation (p < 0.001), and had better health (p < 0.001). The same pattern was found for well-being, except in relation to gender, as men had higher levels (p = 0.016). These variables were found to be correlated. Discussion: Even though active aging is an important strategy to implement, it is indispensable to consider the perceptions and conditions that need to be in place before that. This study reveals that several social and health-related factors are associated with well-being and active aging awareness, as well as the differences between groups that exist in mainland Portugal in relation to that. This emphasizes how vital it is to address social inequalities in active aging efforts, which are not necessarily uncovered when only considering actual active aging measures.


Assuntos
Envelhecimento , Nível de Saúde , Idoso , Masculino , Humanos , Feminino , Portugal , Estudos Transversais , Fatores Socioeconômicos
5.
Pharmaceutics ; 15(4)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37111567

RESUMO

The efficiency of photodynamic therapy is often limited by the scarcity of oxygen at the target site. To address this problem, this work proposes the development of a new nanosystem for antimicrobial photodynamic therapy applications (aPDT) where the natural-origin photosensitizer curcumin (CUR) is immersed in an oxygen-rich environment. Inspired by the perfluorocarbon-based photosensitizer/O2 nanocarriers reported in the literature, we developed a new type of silica nanocapsule containing curcumin dissolved in three hydrophobic ionic liquids (ILs) with high oxygen dissolving capacities. The nanocapsules (CUR-IL@ncSi), prepared by an original oil-in-water microemulsion/sol-gel method, had a high IL content and exhibited clear capacities to dissolve and release significant amounts of oxygen, as demonstrated by deoxygenation/oxygenation studies. The ability of CUR-IL solutions and of CUR-IL@ncSi to generate singlet oxygen (1O2) upon irradiation was confirmed by the detection of 1O2 phosphorescence at 1275 nm. Furthermore, the enhanced capacities of oxygenated CUR-IL@ncSi suspensions to generate 1O2 upon irradiation with blue light were confirmed by an indirect spectrophotometric method. Finally, preliminary microbiological tests using CUR-IL@ncSi incorporated into gelatin films showed the occurrence of antimicrobial effects due to photodynamic inactivation, with their relative efficiencies depending on the specific IL in which curcumin was dissolved. Considering these results, CUR-IL@ncSi has the potential to be used in the future to develop biomedical products with enhanced oxygenation and aPDT capacities.

6.
Polymers (Basel) ; 15(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36771780

RESUMO

Atherosclerosis is one of the leading causes of death worldwide. Although this subject arouses much interest, there are limitations associated with the biomechanical investigation done in atherosclerotic tissues, namely the unstandardized tests for the mechanical characterization of these tissues and the inherent non-consensual results obtained. The variability of tests and typologies of samples hampers direct comparisons between results and hinders the complete understanding of the pathologic process involved in atherosclerosis development and progression. Therefore, a consensual and definitive evaluation of the mechanical properties of healthy and atherosclerotic blood vessels would allow the production of physical biomodels that could be used for surgeons' training and personalized surgical planning. Additive manufacturing (AM), commonly known as 3D printing, has attracted significant attention due to the potential to fabricate biomodels rapidly. However, the existing literature regarding 3D-printed atherosclerotic vascular models is still very limited. Consequently, this review intends to present the atherosclerosis disease and the consequences of this pathology, discuss the mechanical characterization of atherosclerotic vessels/plaques, and introduce AM as a potential strategy to increase the understanding of atherosclerosis treatment and pathophysiology.

7.
J Community Psychol ; 51(4): 1560-1570, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36082530

RESUMO

Resilience is of the upmost importance to deal with everyday problems faced by communities. The concept of community resilience is gaining prominence in disaster management policy and practice, and it has been shown to be an important factor during pandemic recovery such as during the SARS-CoV-2 outbreak. We present an instrument for community resilience assessment adapted for disasters like the pandemics. The instrument was based on the theory-based and evidence-informed Communities Advancing Resilience Toolkit (CART) Assessment Survey, adapted for the first time to Portuguese. Another strong feature of this study relates to the targeted participants, namely human service workers (598). They are key informants for their close involvement with communities. This version of the CART was reliable. A confirmatory factor analysis indicated a good relationship between the observed variables and their underlying latent constructs. Moreover, tests for measurement invariance across participants showed that differences in factor variances and covariances were not attributable to age-based differences in the properties of the scales themselves. Our findings support the fundamental idea that it is worthwhile to have an instrument to measure community resilience. Thus, our study adds to the evaluation of the CART, supporting its value as a robust instrument to measure resilience at the community level in different countries.


Assuntos
COVID-19 , Desastres , Humanos , SARS-CoV-2 , Etnicidade , Análise Fatorial
8.
Int J Mol Sci ; 23(16)2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-36012528

RESUMO

Autism Spectrum Disorders (ASDs) are a group of neurodevelopmental pathologies whose current treatment is neither curative nor effective. Anthocyanins are naturally occurring compounds abundant in blueberries and in other red fruits which have been shown to be successful in the treatment of several neurological diseases, at least in in vitro and in vivo disease models. The aim of the present work was to study the ability of an anthocyanin-rich extract (ARE) obtained from Portuguese blueberries to alleviate autism-like symptoms in a valproic acid (VPA) mouse model of ASD and to get insights into the underlying molecular mechanisms of such benefits. Therefore, pregnant BALB/c females were treated subcutaneously with a single dose of VPA (500 mg/kg) or saline on gestational day 12.5. Male offspring mice were orally treated with the ARE from Portuguese blueberries (30 mg/kg/day) or the vehicle for three weeks, and further subjected to behavioral tests and biochemical analysis. Our data suggested that the ARE treatment alleviated autism-like behaviors in in utero VPA-exposed mice and, at the same time, decreased both neuroinflammation and gut inflammation, modulated the gut microbiota composition, increased serotonin levels in cerebral prefrontal cortex and gut, and reduced the synaptic dysfunction verified in autistic mice. Overall, our work suggests that anthocyanins extracted from Portuguese blueberries could constitute an effective strategy to ameliorate typical autistic behaviors through modulation of the microbiota-gut-brain axis.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Mirtilos Azuis (Planta) , Microbioma Gastrointestinal , Efeitos Tardios da Exposição Pré-Natal , Animais , Antocianinas/farmacologia , Antocianinas/uso terapêutico , Transtorno do Espectro Autista/tratamento farmacológico , Transtorno Autístico/tratamento farmacológico , Eixo Encéfalo-Intestino , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Portugal , Gravidez , Ácido Valproico/farmacologia , Ácido Valproico/uso terapêutico
9.
Pharmaceutics ; 13(3)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804727

RESUMO

The aim of this study was to develop multiparticulate systems with a combination of ezetimibe micellar systems and atorvastatin solid dispersions using croscarmellose as a hydrophilic vehicle and Kolliphor RH40 as a surfactant. The presence of a surfactant with low hydrophilic polymer ratios produces the rapid dissolution of ezetimibe through a drug-polymer interaction that reduces its crystallinity. The solid dispersion of atorvastatin with low proportions of croscarmellose showed drug-polymer interactions sufficient to produce the fast dissolution of atorvastatin. Efficacy studies were performed in diabetic Goto-Kakizaki rats with induced hyperlipidemia. The administration of multiparticulate systems of ezetimibe and atorvastatin at low (2 and 6.7 mg/kg) and high (3 and 10 mg/kg) doses showed similar improvements in levels of cholesterol, triglycerides, lipoproteins, alanine transaminase, and aspartate transaminase compared to the high-fat diet group. Multiparticulate systems at low doses (2 and 6.7 mg/kg of ezetimibe and atorvastatin) had a similar improvement in hepatic steatosis compared to the administration of ezetimibe and atorvastatin raw materials at high doses (3 and 10 mg/kg). These results confirm the effectiveness of solid dispersions with low doses of ezetimibe and atorvastatin to reduce high lipid levels and hepatic steatosis in diabetic rats fed a high-fat diet.

10.
Nutrients ; 12(12)2020 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-33260540

RESUMO

Dietary polyphenols are multi-target compounds that have been considered promising candidates in strategies for the mitigation of neurological diseases, acting particularly through reduction of microglia-driven neuroinflammation. In this study, an anthocyanin-rich extract obtained from Portuguese blueberries was subjected to a simulated gastrointestinal digestion; after chemical characterisation, the potential of both non-digested and digested extracts to combat neuroinflammation was evaluated using a microglia N9 cell line. Although the extracts have markedly different chemical composition, both were efficient in reducing the production of either key inflammatory markers or reactive oxygen species and in enhancing reduced glutathione levels in activated cells. Furthermore, this protection was shown to be related to the suppression of nuclear factor kappa B (NF-kB) activation, and to a signal transducer and activator of transcription 1 (STAT1)-independent mechanism. These results demonstrate that the anthocyanin extract, after simulated digestion, maintains its efficacy against neuroinflammation, and can, therefore, assume a relevant role in prevention of neuroinflammation-related neurological disorders.


Assuntos
Antocianinas/química , Mirtilos Azuis (Planta)/química , Frutas/química , Inflamação/tratamento farmacológico , Microglia/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa/metabolismo , Camundongos , NF-kappa B/genética , NF-kappa B/metabolismo , Extratos Vegetais/química , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/metabolismo , Fator de Necrose Tumoral alfa
11.
Int J Mol Sci ; 21(22)2020 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-33212797

RESUMO

Anthocyanins are naturally occurring polyphenols commonly found in fruits and vegetables. Numerous studies have described that anthocyanin-rich foods may play a crucial role in the prevention and treatment of different pathological conditions, which have encouraged their consumption around the world. Anthocyanins exhibit a significant neuroprotective role, mainly due to their well-recognized antioxidant and anti-inflammatory properties. Neuroinflammation is an intricate process relevant in both homeostatic and pathological circumstances. Since the progression of several neurological disorders relies on neuroinflammatory process, targeting brain inflammation has been considered a promising strategy in those conditions. Recent data have shown the anti-neuroinflammatory abilities of many anthocyanins and of their metabolites in the onset and development of several neurological disorders. In this review, it will be discussed the importance and the applicability of these polyphenolic compounds as neuroprotective agents and it will be also scrutinized the molecular mechanisms underlying the modulation of neuroinflammation by these natural compounds in the context of several brain diseases.


Assuntos
Antocianinas/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Encefalopatias/tratamento farmacológico , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Encefalopatias/metabolismo , Encefalopatias/patologia , Humanos
12.
Sci Signal ; 13(650)2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963013

RESUMO

Alcohol abuse adversely affects the lives of millions of people worldwide. Deficits in synaptic transmission and in microglial function are commonly found in human alcohol abusers and in animal models of alcohol intoxication. Here, we found that a protocol simulating chronic binge drinking in male mice resulted in aberrant synaptic pruning and substantial loss of excitatory synapses in the prefrontal cortex, which resulted in increased anxiety-like behavior. Mechanistically, alcohol intake increased the engulfment capacity of microglia in a manner dependent on the kinase Src, the subsequent activation of the transcription factor NF-κB, and the consequent production of the proinflammatory cytokine TNF. Pharmacological blockade of Src activation or of TNF production in microglia, genetic ablation of Tnf, or conditional ablation of microglia attenuated aberrant synaptic pruning, thereby preventing the neuronal and behavioral effects of the alcohol. Our data suggest that aberrant pruning of excitatory synapses by microglia may disrupt synaptic transmission in response to alcohol abuse.


Assuntos
Ansiedade/fisiopatologia , Comportamento Animal/efeitos dos fármacos , Etanol/administração & dosagem , Plasticidade Neuronal/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos , Animais , Ansiedade/psicologia , Comportamento Animal/fisiologia , Células Cultivadas , Depressores do Sistema Nervoso Central/administração & dosagem , Etanol/sangue , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Plasticidade Neuronal/fisiologia , Sinapses/fisiologia , Transmissão Sináptica/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
13.
Cell Rep ; 31(12): 107796, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32579923

RESUMO

Nervous tissue homeostasis requires the regulation of microglia activity. Using conditional gene targeting in mice, we demonstrate that genetic ablation of the small GTPase Rhoa in adult microglia is sufficient to trigger spontaneous microglia activation, producing a neurological phenotype (including synapse and neuron loss, impairment of long-term potentiation [LTP], formation of ß-amyloid plaques, and memory deficits). Mechanistically, loss of Rhoa in microglia triggers Src activation and Src-mediated tumor necrosis factor (TNF) production, leading to excitotoxic glutamate secretion. Inhibiting Src in microglia Rhoa-deficient mice attenuates microglia dysregulation and the ensuing neurological phenotype. We also find that the Rhoa/Src signaling pathway is disrupted in microglia of the APP/PS1 mouse model of Alzheimer disease and that low doses of Aß oligomers trigger microglia neurotoxic polarization through the disruption of Rhoa-to-Src signaling. Overall, our results indicate that disturbing Rho GTPase signaling in microglia can directly cause neurodegeneration.


Assuntos
Envelhecimento/patologia , Microglia/patologia , Degeneração Neural/patologia , Neurônios/metabolismo , Proteína rhoA de Ligação ao GTP/deficiência , Envelhecimento/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Proteína Tirosina Quinase CSK , Linhagem Celular , Polaridade Celular , Sobrevivência Celular , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Fenótipo , Sinapses/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/metabolismo
14.
Phytochemistry ; 169: 112159, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31600652

RESUMO

In Portugal, the pine black sawyer Monochamus galloprovincialis is the principal vector of the pinewood nematode, Bursaphelenchus xylophilus, the causal agent of pine wilt disease (PWD), a lethal phyopathogen with major ecological and economic consequences to European forestry. The aim of this study was to determine the influence of M. galloprovincialis feeding on the volatiles emitted by pine trees. This study focused on the pine species which are most relevant to Portugal, that is, Pinus pinaster (maritime pine) and Pinus pinea (stone or umbrella pine), assessing to what extent pine chemotypes might influence feeding by the insect vector. Preliminary evaluation of each maritime pine essential oil allowed recognizing the existence of two main chemotypes (C1 and C2) and absence of chemical variability in P. pinea. Emission of volatiles from pine trees was evaluated before and during 24 h of feeding by a mixed-sex pair of newly emerged, unfed M. galloprovincialis. Volatiles were also collected from the oleoresin released from the feeding wounds as well as from the insects after feeding. Pine volatiles were collected by solid phase microextraction (SPME) and insect volatiles extracted with pentane, and all analysed by gas chromatography-mass spectrometry (GC-MS) and by GC for component identification and quantification, respectively. Of the seventeen emitted volatiles detected in SPME analyses of P. pinaster, ß-pinene, α-pinene, ß-caryophyllene, and germacrene D showed the highest average fold increases as a result of M. galloprovincialis feeding. When grouped by P. pinaster chemotype, C1 and C2 groups of trees showed different patterns of responses. ß-Caryophyllene and germacrene D showed the highest fold increase in C1 trees, whereas ß-pinene and α-pinene clearly dominated in C2 trees. Likewise, the oleoresin volatiles from C1 trees were dominated by δ-3-carene and/or ß-pinene, whereas α-pinene and ß-pinene were the main volatile components from oleoresin of C2 trees. Nine components were detected in P. pinea volatiles, of which limonene showed the highest fold increase as a result of insect feeding. The volatiles collected from the insects after they had fed on P. pinaster included α-pinene, ß-pinene, and abietic acid, and by the straight-chain n-alkanes n-C27, n-C29, and n-C25, together with the methyl-branched hydrocarbons 3-meC29, 2-meC28, and 3-meC27. A better understanding of the responses of different P. pinaster chemotypes to feeding by M. galloprovincialis may be helpful in the development of new lures to improve pine sawyer trapping in integrated pest management for control of PWD.


Assuntos
Ração Animal , Besouros/efeitos dos fármacos , Pinus/química , Extratos Vegetais/química , Compostos Orgânicos Voláteis/farmacologia , Animais , Cromatografia Gasosa-Espectrometria de Massas , Portugal , Microextração em Fase Sólida , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/isolamento & purificação
15.
FEMS Microbiol Ecol ; 94(7)2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29718181

RESUMO

Pine Wilt Disease (PWD) has a significant impact on Eurasia pine forests. The microbiome of the nematode (the primary cause of the disease), its insect vector, and the host tree may be relevant for the disease mechanism. The aim of this study was to characterize these microbiomes, from three PWD-affected areas in Portugal, using Denaturing Gradient Gel Electrophoresis, 16S rRNA gene pyrosequencing, and a functional inference-based approach (PICRUSt). The bacterial community structure of the nematode was significantly different from the infected trees but closely related to the insect vector, supporting the hypothesis that the nematode microbiome might be in part inherited from the insect. Sampling location influenced mostly the tree microbiome (P < 0.05). Genes related both with plant growth promotion and phytopathogenicity were predicted for the tree microbiome. Xenobiotic degradation functions were predicted in the nematode and insect microbiomes. Phytotoxin biosynthesis was also predicted for the nematode microbiome, supporting the theory of a direct contribution of the microbiome to tree-wilting. This is the first study that simultaneously characterized the nematode, tree and insect-vector microbiomes from the same affected areas, and overall the results support the hypothesis that the PWD microbiome plays an important role in the disease's development.


Assuntos
Bactérias/classificação , Besouros/microbiologia , Besouros/parasitologia , Pinus/parasitologia , Doenças das Plantas/parasitologia , Rabditídios/microbiologia , Animais , Bactérias/isolamento & purificação , Insetos Vetores/microbiologia , Insetos Vetores/parasitologia , Microbiota/genética , Pinus/microbiologia , Portugal , RNA Ribossômico 16S/genética , Árvores/microbiologia , Árvores/parasitologia
16.
Free Radic Biol Med ; 118: 137-149, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29501565

RESUMO

Hypoxia causes oxidative stress and excitotoxicity, culminating in neuronal damage during brain ischemia. Hypoxia also activates microglia, the myeloid resident cells of the brain parenchyma. Upon activation, microglia release high amounts of the neurotransmitter glutamate, contributing for neuronal excitotoxicity during brain insults. Here, we reveal a signaling pathway controlling glutamate release from human microglia during hypoxia. We show that hypoxia-mediated redox imbalance promotes the activation of endoplasmic reticulum inositol 1,4,5-trisphosphate (InsP3) receptors leading to Ca2+ mobilization into the cytosol. Increasing cytosolic Ca2+ signaling in microglia activates the non-receptor protein tyrosine kinase Src at the plasma membrane. Src activation enhances the permeability of microglial gap junctions promoting the release of glutamate during hypoxia. Preventing the hypoxia-triggered redox imbalance, using the dietary antioxidants neochlorogenic acid or vitamin C, inhibits InsP3-dependent Ca2+ signaling and abrogates the release of glutamate. Overall, modulating microglial Ca2+ signaling in response to changes in the redox microenvironment might be critical for controlling glutamate excitotoxicity during hypoxia.


Assuntos
Sinalização do Cálcio/fisiologia , Ácido Glutâmico/metabolismo , Microglia/metabolismo , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Linhagem Celular , Ácido Clorogênico/análogos & derivados , Ácido Clorogênico/farmacologia , Humanos , Microglia/efeitos dos fármacos , Oxirredução , Ácido Quínico/análogos & derivados , Ácido Quínico/farmacologia
17.
Toxicol Lett ; 283: 21-31, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29129797

RESUMO

Alcohol use disorders affect millions of people worldwide causing huge social and economic burden on modern society. Excessive alcohol consumption or intoxication provokes severe damage to the body inducing immune suppression, liver damage and neurological disorder. In the central nervous system (CNS), alcohol exposure can lead to neuronal loss, cognitive decline, motor dysfunction, inflammation and impairment of neuroimmune responses. Glial cells, from which microglia represent roughly 10-15%, are primary modulators of the neuroimmune responses and inflammation in the CNS. Here we overview literature relating alcohol exposure with microglia activation and brain inflammation, highlighting that microglia are critical regulators of alcohol responses in the CNS. Different studies indicate that alcohol intake alters the microglial activation spectrum, with the microglial response varying according to the dose, duration, and pattern of alcohol administration. Presently, further investigation is required to establish whether microglia dysfunction initiates or simply amplifies the neurotoxicity of alcohol in the brain. Such knowledge can be greatly facilitated by the use of microglia-specific genetic targeting in animal models and will be critical for the development of better therapeutics for mitigating the neurotoxicity induced by alcohol.


Assuntos
Alcoolismo/imunologia , Alcoolismo/patologia , Microglia/imunologia , Microglia/patologia , Síndromes Neurotóxicas/imunologia , Síndromes Neurotóxicas/patologia , Animais , Depressores do Sistema Nervoso Central/toxicidade , Encefalite/patologia , Etanol/toxicidade , Humanos
18.
Sci Rep ; 6: 23908, 2016 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-27045340

RESUMO

Monochamus beetles are the dispersing vectors of the nematode Bursaphelenchus xylophilus, the causative agent of pine wilt disease (PWD). PWD inflicts significant damages in Eurasian pine forests. Symbiotic microorganisms have a large influence in insect survival. The aim of this study was to characterize the bacterial community associated to PWD vectors in Europe and East Asia using a culture-independent approach. Twenty-three Monochamus galloprovincialis were collected in Portugal (two different locations); twelve Monochamus alternatus were collected in Japan. DNA was extracted from the insects' tracheas for 16S rDNA analysis through denaturing gradient gel electrophoresis and barcoded pyrosequencing. Enterobacteriales, Pseudomonadales, Vibrionales and Oceanospirilales were present in all samples. Enterobacteriaceae was represented by 52.2% of the total number of reads. Twenty-three OTUs were present in all locations. Significant differences existed between the microbiomes of the two insect species while for M. galloprovincialis there were no significant differences between samples from different Portuguese locations. This study presents a detailed description of the bacterial community colonizing the Monochamus insects' tracheas. Several of the identified bacterial groups were described previously in association with pine trees and B. xylophilus, and their previously described functions suggest that they may play a relevant role in PWD.


Assuntos
Besouros/microbiologia , Microbiota , Pinus/parasitologia , Doenças das Plantas/parasitologia , Animais , Besouros/parasitologia , DNA/análise , DNA Ribossômico/análise , Eletroforese , Interações Hospedeiro-Parasita , Insetos Vetores/microbiologia , Nematoides , Portugal
19.
Pest Manag Sci ; 70(1): 6-13, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23536470

RESUMO

BACKGROUND: The pinewood nematode (PWN) Bursaphelenchus xylophilus is an important conifer disease worldwide. It is the direct cause of the death of millions of pines in south-east Asia (mainly Japan, China and Korea) and has been established in Portugal since 1999. The phasing out of methyl bromide has created an urgent need for alternative treatment of wood packaging materials. The effect of sulfuryl fluoride (SF), a broad-spectrum fumigant used to control insects, was tested in Pinus pinaster boards naturally infested by PWN. RESULTS: Boards were fumigated for 24 h at three different temperatures (15, 20 and 30 °C) with dosage ranges of 3169-4407, 1901-4051 and 1385-2141 gh m(-3) respectively. Treated wood was sampled for nematode identification and counting, before treatment and after 24 h, 72 h and 21 days. No survival was found in the 15 °C and 30 °C treatments, while at 20 °C the mortality ranged from 94.06 to 100%. Some reasons for the survival at 20 °C are presented. CONCLUSION: Results confirm SF to be an effective quarantine treatment for PWN at 15 and 30 °C. Further studies are needed to obtain the most effective dosage at 20 °C, and to determine the toxicity of SF fumigation on B. xylophilus at other temperatures, especially at 25 °C.


Assuntos
Antinematódeos/farmacologia , Pinus/parasitologia , Doenças das Plantas/parasitologia , Ácidos Sulfínicos/farmacologia , Tylenchida/efeitos dos fármacos , Animais , Doenças das Plantas/prevenção & controle , Tylenchida/fisiologia
20.
Rev Iberoam Micol ; 23(3): 185-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17196027

RESUMO

Ambrosia fungi live associated with beetles (Scolytidae and Platypodidae) in host trees and act as a food source for the insects. The symbiotic relation is important to the colonizing strategies of host trees by beetles. Ambrosia fungi are dimorphic: they grow as ambrosial form and as mycelium. The fungi are highly specialized, adapted to a specific beetle and to the biotope where they both live. In addition other fungi have been found such as tree pathogenic fungi that may play a role in insects host colonization success. Saprophytic fungi are also present in insects galleries. These may decompose cellulose and/or be antagonistic to other less beneficial fungi. This paper summarizes the importance of ambrosia fungi and the interaction with insects and hosts. The possibility of the transport of pathogenic fungi by Platypus cylindrus to cork oak thus contributing for its decline is discussed.


Assuntos
Ascomicetos/fisiologia , Besouros/microbiologia , Fungos Mitospóricos/fisiologia , Quercus/microbiologia , Xylariales/fisiologia , Estruturas Animais/microbiologia , Animais , Ascomicetos/isolamento & purificação , Besouros/anatomia & histologia , Besouros/fisiologia , Feminino , Fungos Mitospóricos/isolamento & purificação , Doenças das Plantas/microbiologia , Portugal , Quercus/fisiologia , Especificidade da Espécie , Simbiose , Madeira/microbiologia , Xylariales/isolamento & purificação
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