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1.
Mol Neurobiol ; 60(2): 851-863, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36378469

RESUMO

Astrocytes are key glial cells for the metabolic and functional support of the brain. Mitochondrial quality control (MQC), in particular the balance between mitophagy and mitochondrial biogenesis, is a major event for the maintenance of cellular homeostasis. Carbon monoxide (CO) is an endogenous gasotransmitter that inhibits cell death and inflammation by targeting mitochondria. It is well established that CO promotes cytoprotection by increasing mitochondrial population and metabolism (oxidative phosphorylation). Thus, it is hypothesized that CO-induced cytoprotection may also be mediated by the balance between mitophagy and mitochondrial biogenesis. Herein, the carbon monoxide releasing molecule-A1 (CORM-A1) was used in primary cultures of astrocytes to assess CO role on mitochondrial turnover. PINK1/Parkin-dependent mitophagy was stimulated by CORM-A1 following 1 h of treatment. While at 24 h after treatment, CORM-A1 increased mitochondrial population, which may indicate mitochondrial biogenesis. In fact, mitochondrial biogenesis was confirmed by the enhancement of PGC-1α expression that upregulates several mitochondrial transcription factors. Furthermore, inhibition of mitophagy by knocking down PINK1 expression reverted CO-induced mitochondrial biogenesis, indicating that mitochondrial turnover is dependent on modulation of mitophagy. Finally, CORM-A1 prevented astrocytic cell death induced by oxidative stress in a mitophagy-dependent manner. In fact, whenever PINK1 was knocked down, CORM-A1-induced cytoprotection was lost. In summary, CORM-A1 stimulates mitochondrial turnover, which in turn prevents astrocytic cell death. CO cytoprotection depends on increasing mitochondrial population and on eliminating dysfunctional mitochondria.


Assuntos
Monóxido de Carbono , Mitofagia , Monóxido de Carbono/farmacologia , Monóxido de Carbono/metabolismo , Astrócitos/metabolismo , Biogênese de Organelas , Estresse Oxidativo , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
2.
Vaccines (Basel) ; 10(8)2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-36016173

RESUMO

BACKGROUND: quadrivalent inactivated vaccine (QIV) has replaced trivalent inactivated vaccine (TIV). In Portugal, TIV is free of charge for risk groups, including older adults (≥65 years old). In its turn, QIV-which provides broader protection as it includes an additional lineage B strain-was introduced in Portugal in October 2018; only since the 2019/20 influenza season has it been provided free of charge for risk groups. This study evaluates the cost effectiveness of switching from TIV to QIV, from the National Health Service perspective, in the Portuguese elderly mainland population. METHODS: A decision tree model was developed to compare TIV and QIV, based on Portuguese hospitalization data for the 2015/16 influenza season. The primary health economic outcome under consideration was the incremental cost-effectiveness ratio (ICER). In addition, one-way sensitivity analysis and probabilistic sensitivity analysis were performed. RESULTS: the high cost of QIV (approximately three times the cost of TIV) would lead to a total increment of EUR 5,283,047, and the resulting ICER would be EUR 26,403,007/QALY, above the usual willingness-to-pay threshold. CONCLUSIONS: from the National Health Service perspective, our findings reveal that QIV is not cost effective for the Portuguese elderly population due to the high cost. If the QIV costs were the same as the TIV, then QIV would be cost effective.

3.
J Clin Med ; 10(10)2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-34063514

RESUMO

BACKGROUND: Analysis of retinal microaneurysm turnover (MAT) has been previously shown to contribute to the identification of eyes at risk of developing clinically significant complications associated with diabetic retinopathy (DR). We propose to further characterize MAT as a predictive biomarker of DR progression and development of vision-threatening complications. METHODS: 212 individuals with type 2 diabetes (T2D; ETDRS grades 20 and 35) were evaluated annually in a 5-year prospective, longitudinal study, by color fundus photography and optical coherence tomography. Endpoints were diabetic macular edema (DME) or proliferative retinopathy (PDR). MAT analysis included determination of MA formation and disappearance rates, automatically assessed using the RetMarkerDR®. Retinopathy severity progression was evaluated using step increases in ETDRS severity levels. RESULTS: Of the 212 individuals, 172 completed the 5-year follow-up study or developed an endpoint (n = 27). MAT calculated at 1 year showed a significant difference between groups of endpoint developments (p = 0.018), particularly MA disappearance rate (p = 0.007). MAT also showed a significant difference between eyes with different ETDRS severity progression in the 5-year period (p = 0.035). CONCLUSIONS: MAT is an indicator of the development of DME and/or PDR as well as of DR severity progression in T2D individuals with mild retinopathy.

4.
J Clin Med ; 10(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070479

RESUMO

To examine retinal vessel closure metrics and neurodegenerative changes occurring in the initial stages of nonproliferative diabetic retinopathy (NPDR) and severity progression in a three-year period. Methods: Three-year prospective longitudinal observational cohort of individuals with type 2 diabetes (T2D), one eye per person, using spectral domain-optical coherence tomography (SD-OCT) and OCT-Angiography (OCTA). Eyes were examined four times with one-year intervals. OCTA vessel density maps of the retina were used to quantify vessel closure. Thickness of the ganglion cell + inner plexiform layer (GCL + IPL) was examined to identify retinal neurodegenerative changes. Diabetic retinopathy ETDRS classification was performed using the seven-field ETDRS protocol. Results: A total of 78 eyes/patients, aged 52 to 80 years, with T2D and ETDRS grades from 10 to 47 were followed for 3 years with annual examinations. A progressive increase in retinal vessel closure was observed. Vessel density (VD) showed higher decreases with retinopathy worsening demonstrated by step-changes in ETDRS severity scale (p < 0.001). No clear correlation was observed between neurodegenerative changes and retinopathy progression. Conclusions: Retinal vessel closure in NPDR correlates with DR severity progression. Our findings provide supporting evidence that OCTA metrics of vessel closure may be used as a surrogate for DR severity progression.

5.
BMC Med Res Methodol ; 21(1): 54, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33731014

RESUMO

BACKGROUND: Recruiting asymptomatic participants with early disease stages into studies is challenging and only little is known about facilitators and barriers to screening and recruitment of study participants. Thus we assessed factors associated with screening rates in the MACUSTAR study, a multi-centre, low-interventional cohort study of early stages of age-related macular degeneration (AMD). METHODS: Screening rates per clinical site and per week were compiled and applicable recruitment factors were assigned to respective time periods. A generalized linear mixed-effects model including the most relevant recruitment factors identified via in-depth interviews with study personnel was fitted to the screening data. Only participants with intermediate AMD were considered. RESULTS: A total of 766 individual screenings within 87 weeks were available for analysis. The mean screening rate was 0.6 ± 0.9 screenings per week among all sites. The participation at investigator teleconferences (relative risk increase 1.466, 95% CI [1.018-2.112]), public holidays (relative risk decrease 0.466, 95% CI [0.367-0.591]) and reaching 80% of the site's recruitment target (relative risk decrease 0.699, 95% CI [0.367-0.591]) were associated with the number of screenings at an individual site level. CONCLUSIONS: Careful planning of screening activities is necessary when recruiting early disease stages in multi-centre observational or low-interventional studies. Conducting teleconferences with local investigators can increase screening rates. When planning recruitment, seasonal and saturation effects at clinical site level need to be taken into account. TRIAL REGISTRATION: ClinicalTrials.gov NCT03349801 . Registered on 22 November 2017.


Assuntos
Degeneração Macular , Estudos de Coortes , Humanos , Pesquisadores
6.
Front Neurosci ; 15: 800004, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35757010

RESUMO

Diabetic retinopathy (DR) has been considered a microvascular disease, but it has become evident that neurodegeneration also plays a key role in this complex pathology. Indeed, this complexity is reflected in its progression which occurs at different rates in different type 2 diabetic (T2D) individuals. Based on this concept, our group has identified three DR progression phenotypes that might reflect the interindividual differences: phenotype A, characterized by low microaneurysm turnover (MAT <6), phenotype B, low MAT (<6) and increased central retinal thickness (CRT); and phenotype C, with high MAT (≥6). In this study, we evaluated the progression of DR neurodegeneration, considering ganglion cell+inner plexiform layers (GCL+IPL) thinning, in 170 T2D individuals followed for a period of 5 years, to explore associations with disease progression or risk phenotypes. Ophthalmological examinations were performed at baseline, first 6 months, and annually. GCL+IPL average thickness was evaluated by optical coherence tomography (OCT). Microaneurysm turnover (MAT) was evaluated using the RetMarkerDR. ETDRS level and severity progression were assessed in seven-field color fundus photography. In the overall population there was a significant loss in GCL+IPL (-0.147 µm/year), independently of glycated hemoglobin, age, sex, and duration of diabetes. Interestingly, this progressive thinning in GCL + IPL reached higher values in phenotypes B and C (-0.249 and -0.238 µm/year, respectively), whereas phenotype A remained relatively stable. The presence of neurodegeneration in all phenotypes suggests that it is the retinal vascular response to the early neurodegenerative changes that determines the course of the retinopathy in each individual. Therefore, classification of different DR phenotypes appears to offer relevant clarification of DR disease progression and an opportunity for improved management of each T2D individual with DR, thus playing a valuable role for the implementation of personalized medicine in DR.

7.
Arch. Clin. Psychiatry (Impr.) ; 40(4): 129-134, 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-686096

RESUMO

BACKGROUND: Significant deficits in emotional recognition and social perception characterize patients with schizophrenia and have direct negative impact both in inter-personal relationships and in social functioning. Virtual reality, as a methodological resource, might have a high potential for assessment and training skills in people suffering from mental illness. OBJECTIVES: To present preliminary results of a facial emotional recognition assessment designed for patients with schizophrenia, using 3D avatars and virtual reality. METHODS: Presentation of 3D avatars which reproduce images developed with the FaceGen® software and integrated in a three-dimensional virtual environment. Each avatar was presented to a group of 12 patients with schizophrenia and a reference group of 12 subjects without psychiatric pathology. RESULTS: The results show that the facial emotions of happiness and anger are better recognized by both groups and that the major difficulties arise in fear and disgust recognition. Frontal alpha electroencephalography variations were found during the presentation of anger and disgust stimuli among patients with schizophrenia. DISCUSSION: The developed program evaluation module can be of surplus value both for patient and therapist, providing the task execution in a non anxiogenic environment, however similar to the actual experience.


CONTEXTO: Pessoas diagnosticadas com esquizofrenia apresentam um défice significativo na cognição social com implicações negativas relativamente ao funcionamento interpessoal e social. A realidade virtual apresenta grandes potencialidades para a avaliação e o treino de competências em pessoas com doença mental. OBJETIVOS: Apresentar os resultados preliminares de um programa construído para avaliação do reconhecimento emocional de faces por pessoas com esquizofrenia, utilizando avatares 3D e realidade virtual. MÉTODOS: Apresentação de avatares 3D que reproduzem expressões emocionais, construídas por meio do FaceGen® e integradas num ambiente virtual tridimensional. Apresentou-se cada avatar a 12 doentes com esquizofrenia e a 12 pessoas sem patologia psiquiátrica, avaliando as respostas de reconhecimento e a atividade eletroencefalográfica frontal. RESULTADOS: Os resultados demonstraram que as expressões de alegria e raiva foram as mais bem reconhecidas pelos dois grupos, enquanto de medo e nojo foram as de maior dificuldade. Verificaram-se alterações na atividade alfa frontal para os estímulos raiva e nojo na amostra de doentes com esquizofrenia. CONCLUSÃO: Apesar de algumas expressões emocionais poderem ser melhoradas, o programa desenvolvido pode constituir uma mais-valia para o paciente e para o terapeuta, proporcionando a execução da tarefa em condições não ansiogênicas e aproximadas à experiência real.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Esquizofrenia , Reconhecimento Fisiológico de Modelo , Simulação por Computador , Cognição , Terapia de Exposição à Realidade Virtual
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