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1.
Health Expect ; 27(1): e13917, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38375962

RESUMO

INTRODUCTION: Patient and public involvement (PPI) initiatives involving patients with chronic respiratory disease (CRD) are rare. Therefore, this study aimed to explore the perspectives of patients with CRD, carers and interested citizens regarding the relevance and need for a PPI network and suggestions for its implementation. METHODS: A qualitative study based on focus groups was conducted. Recruitment occurred through invitations on social media platforms and to patients who have participated in previous asthma studies of the team. Three focus groups were conducted, via video conference, using a semi-structured guide. Thematic analysis was performed by two independent researchers and discussed with the extended team. RESULTS: Fifteen patients with CRD, one carer and one interested citizen (13 females, median 36 (range: 18-72) years) participated. All participants acknowledged the importance of implementing a collaborative network and demonstrated interest in being integrated. Participants acknowledged the importance of their involvement in several phases of the research cycle. The main aim identified for this network was to facilitate communication between patients and researchers. Participants regarded the integration of patients, carers, researchers and healthcare professionals from different scientific areas as relevant. The use of digital platforms to attract members and support the work, together with group dynamics and regular meetings, were some of the most relevant practical considerations for implementing the network. The identified facilitators for their engagement were sharing experiences, researchers' and healthcare professionals' support and feedback and schedule flexibility. The identified barriers included the amount of time dedicated, low health/digital literacy and the potential detachment of nondiagnosed patients or those with low symptom impact in daily life. CONCLUSION: Patients, carers and citizens acknowledged the relevance of implementing a collaborative network and demonstrated interest in active participation in every stage of the health research cycle. A deeper knowledge of the barriers and facilitators identified in this study could support implementing these initiatives in Portugal. PATIENT OR PUBLIC CONTRIBUTION: This study was designed by a research team that included one patient with asthma and one carer. They were specifically involved in building the study protocol and the interview guide. They also gave feedback regarding the electronic consent form and the short sociodemographic questionnaire created, namely by removing noncontributing words or phrases and rewording expressions. The lay summary was written by another patient with asthma. All participants of this study were invited to implement and integrate the ConectAR network-a collaborative network of research in respiratory health. PUBLIC SUMMARY: In Portugal, chronic respiratory patients do not have an active role as 'coinvestigators'. This study aimed to acknowledge if patients and citizens considered a patient and public involvement network useful, whose main purpose would be to facilitate communication between patients and researchers. A study based on online group interviews was carried out with patients with chronic respiratory diseases and interested citizens, both recruited on social media platforms. Participants considered that bringing together patients, carers, researchers and healthcare professionals is valuable because sharing different experiences and perspectives may help patients to improve their daily lives and increase research quality. In conclusion, patients agree that implementing a collaborative network with researchers and healthcare professionals and participating in the health research cycle is quite preponderant. Acknowledging what can help and deter this network may be beneficial to implementing this type of initiative in Portugal.


Assuntos
Asma , Doenças Respiratórias , Feminino , Humanos , Cuidadores , Pesquisa Qualitativa , Pessoal de Saúde , Asma/terapia
2.
Cell Mol Life Sci ; 79(8): 457, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35907034

RESUMO

The contribution of astrocytes to Alzheimer's disease (AD) is still ill defined. AD involves an abnormal accumulation of amyloid-ß peptides (Aß) and increased production of danger signals such as ATP. ATP can direct or indirectly, through its metabolism into adenosine, trigger adaptive astrocytic responses resulting from intracellular Ca2+ oscillations. AD also triggers an upregulation of astrocytic adenosine A2A receptors (A2AR), which blockade prevents memory dysfunction in AD. We now investigated how Aß peptides affect ATP-mediated Ca2+ responses in astrocytes measured by fluorescence live-cell imaging and whether A2AR control astrocytic Ca2+ responses mediated by ATP receptors, mainly P2X7R and P2Y1R. In primary cultures of rat astrocytes exposed to Aß1-42, ATP-evoked Ca2+ responses had a lower amplitude but a longer duration than in control astrocytes and involved P2X7R and P2Y1R, the former potentiating the later. Moreover, Aß1-42 exposure increased protein levels of P2Y1R in astrocytes. A2AR antagonism with SCH58261 controlled in a protein kinase A-dependent manner both P2X7R- and P2Y1R-mediated Ca2+ responses in astrocytes. The interplay between these purinoceptors in astrocytes was blunted upon exposure to Aß1-42. These findings uncover the ability of A2AR to regulate the inter-twinned P2X7R- and P2Y1R-mediated Ca2+ dynamics in astrocytes, which is disrupted in conditions of early AD.


Assuntos
Doença de Alzheimer , Astrócitos , Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Astrócitos/metabolismo , Cálcio/metabolismo , Células Cultivadas , Fragmentos de Peptídeos , Ratos , Receptor A2A de Adenosina/metabolismo , Receptores Purinérgicos P2X7 , Receptores Purinérgicos P2Y1
3.
Purinergic Signal ; 18(2): 199-204, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35476241

RESUMO

Anxiety involves abnormal glucocorticoid signalling and altered glia-neuron communication in brain regions processing emotional responses. Adenosine A2A receptor (A2AR) blockade ameliorates mood and memory impairments by preventing synaptic dysfunction and astrogliosis. Since the glucocorticoid dexamethasone (DEX) can mimic early life-stress conditions, leading to anxiety-like behaviours, we now tested if A2AR blockade prevents alterations in the morphology and function of astrocytes exposed to DEX. Cultured astrocytes exposed to DEX exhibited an up-regulation of astrocytic markers (GFAP, connexin-43 and glutamine synthetase), as well as of A2AR. Moreover, DEX enhanced ATP and glutamate release and increased basal astrocytic Ca2+ levels. The selective A2AR antagonist SCH58261 prevented DEX-induced alterations in ATP release and basal Ca2+ levels but did not affect DEX-induced alteration of glutamate release and astrocytic markers. These findings suggest that alterations in astrocytes function, which might contribute to abnormal glucocorticoid brain signalling, are controlled by A2AR, and therefore, reinforce the relevance of A2AR as a potential therapeutic target to manage mood disorders.


Assuntos
Adenosina , Astrócitos , Adenosina/farmacologia , Trifosfato de Adenosina , Dexametasona/farmacologia , Glucocorticoides , Ácido Glutâmico , Receptor A2A de Adenosina
4.
Pharmacol Res ; 162: 105253, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33080321

RESUMO

This review discusses the evidence supporting a role for ATP signaling (operated by P2X and P2Y receptors) and adenosine signaling (mainly operated by A1 and A2A receptors) in the crosstalk between neurons, astrocytes, microglia and oligodendrocytes. An initial emphasis will be given to the cooperation between adenosine receptors to sharpen information salience encoding across synapses. The interplay between ATP and adenosine signaling in the communication between astrocytes and neurons will then be presented in context of the integrative properties of the astrocytic syncytium, allowing to implement heterosynaptic depression processes in neuronal networks. The process of microglia 'activation' and its control by astrocytes and neurons will then be analyzed under the perspective of an interplay between different P2 receptors and adenosine A2A receptors. In spite of these indications of a prominent role of purinergic signaling in the bidirectional communication between neurons and glia, its therapeutical exploitation still awaits obtaining an integrated view of the spatio-temporal action of ATP signaling and adenosine signaling, clearly distinguishing the involvement of both purinergic signaling systems in the regulation of physiological processes and in the control of pathogenic-like responses upon brain dysfunction or damage.


Assuntos
Trifosfato de Adenosina/metabolismo , Comunicação Celular , Neuroglia/fisiologia , Neurônios/fisiologia , Animais , Humanos , Transdução de Sinais
5.
Int J Syst Evol Microbiol ; 67(5): 1339-1348, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28109203

RESUMO

Strain NL19T is a Gram-stain-negative, aerobic bacterium that was isolated from sludge of a deactivated uranium mine in Portugal. 16S rRNA gene sequence analysis revealed that strain NL19T is a member of the genus Pedobacter and closely related to the strains Pedobacter himalayensis MTCC 6384T, Pedobacter cryoconitis DSM 14825T, Pedobacter westerhofensis DSM 19036T and Pedobacterhartonius DSM 19033T. It had a DNA G+C content of 40.8 mol%, which agreed with the genus description. The main fatty acids included C16 : 1ω7c, C14 : 1ω5c, C4 : 0, iso-C17 : 0, iso-C17 : 0 3-OH, C16 : 0, anteiso-C15 : 0 and iso-C15 : 0 3-OH. The main lipids present were phospholipids (60 %) and sphingolipids (35 %). The most abundant phospholipids included phosphatidylethanolamine, phosphatidylinositol and phosphatidylcholine. Menaquinone-7 (MK-7) was the only isoprenoid quinone detected. DNA-DNA hybridization similarities between strain NL19T and Pedobacter himalayensis MTCC 6384T, Pedobacter cryoconitis DSM 14825T, Pedobacter westerhofensis DSM 19036T and Pedobacter hartonius DSM 19033T were 15.3 , 16.2 , 11.5 and 16.0 %, respectively. Strain NL19T can also be distinguished from these four species based on gyrB and intergenic transcribed spacers (ITS) sequences and by some phenotypic traits such as NaCl tolerance, pH, growth temperature and carbon source utilization. Strain NL19Trepresents a novel species of the genus Pedobacter, for which the name Pedobacter lusitanus sp. nov. is proposed. The type strain is NL19T (=LMG 29220T=CECT 9028T). An amended description of Pedobacter himalayensis is also included.


Assuntos
Mineração , Pedobacter/classificação , Filogenia , Esgotos/microbiologia , Urânio , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , DNA Espaçador Ribossômico/genética , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , Pedobacter/genética , Pedobacter/isolamento & purificação , Fosfolipídeos/química , Portugal , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Esfingolipídeos , Vitamina K 2/análogos & derivados , Vitamina K 2/química
6.
Breathe (Sheff) ; 20(1): 230173, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38482185

RESUMO

ConectAR has demonstrated the feasibility and value of involving patients with chronic respiratory diseases and caregivers as co-researchers, actively considering their perspectives from project inception to implementation and dissemination https://bit.ly/3Oq13se.

7.
Cell Discov ; 10(1): 81, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39103336

RESUMO

The glymphatic-lymphatic system is increasingly recognized as fundamental for the homeostasis of the brain milieu since it defines cerebral spinal fluid flow in the brain parenchyma and eliminates metabolic waste. Animal and human studies have uncovered several important physiological factors regulating the glymphatic system including sleep, aquaporin-4, and hemodynamic factors. Yet, our understanding of the modulation of the glymphatic system is limited, which has hindered the development of glymphatic-based treatment for aging and neurodegenerative disorders. Here, we present the evidence from fluorescence tracing, two-photon recording, and dynamic contrast-enhanced magnetic resonance imaging analyses that 40 Hz light flickering enhanced glymphatic influx and efflux independently of anesthesia and sleep, an effect attributed to increased astrocytic aquaporin-4 polarization and enhanced vasomotion. Adenosine-A2A receptor (A2AR) signaling emerged as the neurochemical underpinning of 40 Hz flickering-induced enhancement of glymphatic flow, based on increased cerebrofluid adenosine levels, the abolishment of enhanced glymphatic flow by pharmacological or genetic inactivation of equilibrative nucleotide transporters-2 or of A2AR, and by the physical and functional A2AR-aquaporin-4 interaction in astrocytes. These findings establish 40 Hz light flickering as a novel non-invasive strategy of enhanced glymphatic flow, with translational potential to relieve brain disorders.

8.
ACS Chem Neurosci ; 14(7): 1299-1309, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-36881648

RESUMO

Increased ATP release and its extracellular catabolism through CD73 (ecto-5'-nucleotidase) lead to the overactivation of adenosine A2A receptors (A2AR), which occurs in different brain disorders. A2AR blockade blunts mood and memory dysfunction caused by repeated stress, but it is unknown if increased ATP release coupled to CD73-mediated formation of extracellular adenosine is responsible for A2AR overactivation upon repeated stress. This was now investigated in adult rats subject to repeated stress for 14 consecutive days. Frontocortical and hippocampal synaptosomes from stressed rats displayed an increased release of ATP upon depolarization, coupled to an increased density of vesicular nucleotide transporters and of CD73. The continuous intracerebroventricular delivery of the CD73 inhibitor α,ß-methylene ADP (AOPCP, 100 µM) during restraint stress attenuated mood and memory dysfunction. Slice electrophysiological recordings showed that restraint stress decreased long-term potentiation both in prefrontocortical layer II/III-layer V synapses and in hippocampal Schaffer fibers-CA1 pyramid synapses, which was prevented by AOPCP, an effect occluded by adenosine deaminase and by the A2AR antagonist SCH58261. These results indicate that increased synaptic ATP release coupled to CD73-mediated formation of extracellular adenosine contributes to mood and memory dysfunction triggered by repeated restraint stress. This prompts considering interventions decreasing ATP release and CD73 activity as novel strategies to mitigate the burden of repeated stress.


Assuntos
5'-Nucleotidase , Adenosina , Animais , Ratos , 5'-Nucleotidase/metabolismo , Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Receptor A2A de Adenosina/metabolismo , Sinapses/metabolismo , Sinaptossomos/metabolismo , Estresse Fisiológico , Fenômenos Eletrofisiológicos
9.
J Fungi (Basel) ; 9(8)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37623608

RESUMO

Candida auris is an opportunistic human pathogen that has rapidly spread to multiple countries and continents and has been associated with a high number of nosocomial outbreaks. Herein, we report the first case of C. auris in Portugal, which was associated with a patient transferred from Angola to an ICU in Portugal for liver transplantation after a SARS-CoV-2 infection. C. auris was isolated during the course of bronchoalveolar lavage, and it was subjected to antifungal susceptibility testing and whole-genome sequence analysis. This isolate presents low susceptibility to azoles and belongs to the genetic clade III with a phylogenetic placement close to African isolates. Although clade III has already been reported in Europe, taking into account the patient's clinical history, we cannot discard the possibility that the patient's colonization/infection occurred in Angola, prior to admission in the Portuguese hospital. Considering that C. auris is a fungal pathogen referenced by WHO as a critical priority, this case reinforces the need for continuous surveillance in a hospital setting.

10.
Mol Neurobiol ; 58(12): 6232-6248, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34476674

RESUMO

Increasing evidence implicates astrocytes and the associated purinergic modulation in Alzheimer's disease (AD), characterized by cognitive deficits involving the extracellular amyloid-ß peptides (Aß) accumulation. Aß can affect astrocytic gliotransmitters release, namely ATP, which is rapidly metabolized into adenosine by ecto-5'-nucleotidase, CD73, resulting in adenosine A2A receptors (A2AR) activation that bolsters neurodegeneration. AD's brains exhibit an upregulation of A2AR and of connexin 43 (Cx43), which in astrocytes forms hemichannels that can mediate ATP release. However, a coupling between astrocytic A2AR and Cx43 remains to be established. This was now investigated using astrocytic primary cultures exposed to Aß1-42 peptides. Aß triggered ATP release through Cx43 hemichannels, a process blocked by A2AR antagonists and mimicked by selective A2AR activation. A2AR directly regulated hemichannels activity and prevented Cx43 upregulation and phosphorylation observed in Aß1-42-exposed astrocytes. Moreover, a proximity ligand assay revealed a physical association between astrocytic A2AR and Cx43. Finally, the blockade of CD73-mediated extracellular formation of ATP-derived adenosine prevented the Aß-induced increase of Cx43 hemichannel activity and of ATP release. Overall, the data identify a feed-forward loop involving astrocytic A2AR and Cx43 hemichannels, whereby A2AR increase Cx43 hemichannel activity leading to increased ATP release, which is converted into adenosine by CD73, sustaining the increased astrocytic A2AR activity in AD-like conditions.


Assuntos
Trifosfato de Adenosina/metabolismo , Peptídeos beta-Amiloides/farmacologia , Astrócitos/metabolismo , Conexina 43/metabolismo , Receptor A2A de Adenosina/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Fosforilação , Ratos , Ratos Wistar
11.
Front Cell Neurosci ; 15: 639322, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33732112

RESUMO

Depressive conditions precipitated by repeated stress are a major socio-economical burden in Western countries. Previous studies showed that ATP-P2X7 receptors (P2X7R) and adenosine A2A receptors (A2AR) antagonists attenuate behavioral modifications upon exposure to repeated stress. Since it is unknown if these two purinergic modulation systems work independently, we now investigated a putative interplay between P2X7R and A2AR. Adult rats exposed to restraint stress for 14 days displayed an anxious (thigmotaxis, elevated plus maze), depressive (anhedonia, increased immobility), and amnesic (modified Y maze, object displacement) profile, together with increased expression of Iba-1 (a marker of microglia "activation") and interleukin-1ß (IL1ß) and tumor necrosis factor α (TNFα; proinflammatory cytokines) and an up-regulation of P2X7R (mRNA) and A2AR (receptor binding) in the hippocampus and prefrontal cortex. All these features were attenuated by the P2X7R-preferring antagonist brilliant blue G (BBG, 45 mg/kg, i.p.) or by caffeine (0.3 g/L, p.o.), which affords neuroprotection through A2AR blockade. Notably, BBG attenuated A2AR upregulation and caffeine attenuated P2X7R upregulation. In microglial N9 cells, the P2X7R agonist BzATP (100 µM) or the A2AR agonist CGS26180 (100 nM) increased calcium levels, which was abrogated by the P2X7R antagonist JNJ47965567 (1 µM) and by the A2AR antagonist SCH58261 (50 nM), respectively; notably JNJ47965567 prevented the effect of CGS21680 and the effect of BzATP was attenuated by SCH58261 and increased by CGS21680. These results provide the first demonstration of a functional interaction between P2X7R and A2AR controlling microglia reactivity likely involved in behavioral adaptive responses to stress and are illustrative of a cooperation between the two arms of the purinergic system in the control of brain function.

12.
Eur J Echocardiogr ; 9(1): 181-3, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18267920

RESUMO

Primary tumours of the heart are uncommon entities, cardiac myxomas being the most frequent. However, mitral valve myxomas are exceptionally rare. In the last 12 years, there have been 25 myxomas diagnosed at our institution, with only two of them originating from the mitral valve. Both patients were female, the first, 25, and the second, 72 years old. The younger patient was very symptomatic with a large mass, 4 cm long, which involved both leaflets causing significant obstruction to the left ventricular inflow. The second one had a smaller mass located at the atrial side of the posterior leaflet that only produced some flow divergence. Neither of them had constitutional nor embolic symptoms. Both patients were submitted to emergent surgical resection that in the first case involved the mitral valve and replacement with mechanical prosthesis. The macroscopic appearance of these tumours suggested a malignant aetiology which may represent somewhat different features of the myxomas when originating from the cardiac valves. Both patients are well reflecting the good prognosis of this illness after resection, although the younger patient was re-operated because of prosthetic valve obstruction and suspicion of recurrence that was not confirmed. Because of the illustrative images and different presentations, we found it interesting to report and discuss them together.


Assuntos
Neoplasias Cardíacas/diagnóstico por imagem , Valva Mitral/cirurgia , Mixoma/diagnóstico por imagem , Adulto , Idoso , Feminino , Neoplasias Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca , Humanos , Mixoma/cirurgia , Ultrassonografia
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