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- 1-Methylcyclopropene and lemongrass essential oil nanocoatings effect on the preservation of cold stored ‘Rocha’ pearPublication . Gago, Custódia; Guerreiro, Adriana; Cruz, Sandra; Martins, Nuno; Cabrita, Maria João; Miguel, Maria; Faleiro, Maria Leonor; Antunes, Maria DulceThe effects of coating 'Rocha' pear with alginate-based nanoemulsions enriched with lemongrass essential oil (LG) was evaluated and compared to the usual 1-MCP treatment. Fruit were treated with 1-MCP (312 nL L-1) or coated with nanoemulsions: sodium alginate 2 % (w/w) + lemongrass essential oil 1.25 % (w/w) (LG 1.25 %) or lemongrass essential oil 2.5 % (w/w) (LG 2.5 %). Then, fruit were stored at 0 degrees C and 90-95 % relative humidity (RH), for eight months. Fruit samples were collected at harvest and after two, four, six and eight months of cold storage, and then transferred to shelf-life at 22 degrees C. Upon removal and after 7 d shelf-life, fruit symptoms of superficial scald and internal browning, ethylene production, color CIE (L*, hue), firmness, soluble solids content (SSC), titratable acidity (TA), weight loss, electrolytic leakage (EL), antioxidant activity and fatty acids of pear peel, microbial growth and sensory analyses were evaluated. Coatings and 1-MCP reduced fruit color evolution and preserved better firmness than control. Coatings and 1-MCP did not affect SSC and TA. Treatments did not influence the sensory quality. Microbial growth was within the safety limits in all treatments. Treatments with 1-MCP and LG-nanoemulsions were similarly efficient to reduce superficial scald, nevertheless the LG-nanoemulsions showed higher internal disorders after 8 months of storage and LG 2.5 % had higher decay at the same period, similar to control. 1-MCP treated fruit had the lowest softening rate after shelf-life up to 4 months and LG 2.5 % showed higher weight loss. Also, ethylene production was higher in control and LG 1.25 % up to 6 months plus shelf-life, while after 8 months there was no difference among treatments. This study suggests that 1-MCP is the most efficient for preserving quality of 'Rocha' pear for 8 months, while up to 6 months the best effect is obtained with LG 1.25 % nanocoatings.
- Activity induced genes expression is impaired in polyglutamine spinocerebellar ataxiasPublication . Torquato Afonso, Inês; Vilhena Catarino Brito, David; Bading, Hilmar; Nóbrega, ClévioPolyglutamine Spinocerebellar ataxias (SCAs) are a group of 6 incurable genetic disorders, caused by an expansion of the trinucleotide cytosine-adenine-guanine in their causative genes, which produces a protein with an expanded glutamine region. This project focuses on the study of Spinocerebellar ataxia type 2 (SCA2) and type 3 (SCA3) (1), which are rare dominantly inherited disorders that primarily impair the cerebellum therefore leading to motor ataxia. Activity-induced inhibitor of death (AID), are a group of pro-survival 9 genes which were found to be neuroprotector in several neurological disorders, including stroke, glaucoma, AD, HD, and ALS (2). In this project, we aim to investigate about the relevance of the expression of AID genes for cerebellum function and whether their expression levels are impaired in SCA2 and SCA3
- Advanced therapy medicinal products development - from guidelines to medicines in the marketPublication . Frederico, Catarina; Vieira da Conceição, André Filipe; Nóbrega, Clévio; Mendonça, Liliana S.In Europe, Advanced Therapy Medicinal Products (ATMPs) include medicines based on gene therapy, somaticcell therapy, tissue-engineered products, and combined ATMPs. ATMPs constitute an emerging and innovative class of medicines used to treat multiple pathologies and are particularly relevant in pathologies where therapeutic options are limited and require high medical needs. These therapies act, among others, through the insertion of recombinant nucleic acids, including genes, to promote a therapeutic effect and through the restoration of cell functions, and repairing or replacing damaged cells and tissues impaired in pathological conditions. Despite their unique potential, these therapies face challenges related to scientific complexity, production processes, regulatory approval, and market access that hinder their development and availability. Based on official European guidelines, the present review explores the current regulatory framework for the non-clinical and clinical development of advanced therapies. We aimed to discuss the regulations applied to the different types of ATMPs, as well as the challenges associated with their development until these therapies reach the market. Accordingly, topics such as the implementation of proof-of-concept studies to provide evidence supporting the potential clinical effect; biodistribution studies to evaluate tissue distribution and persistence; and toxicology studies to assess potential undesirable effects, integration potential of viral vectors, tumorigenicity, and germline transmission, are discussed. This work also covers some of the ATMPs available to patients on the EU market.
- Advancing glioblastoma research with innovative brain organoid-based modelsPublication . Dias Correia, Cátia; Calado, Sofia; Matos, Alexandra; Oleiro Esteves, Filipa Alexandra; De Sousa-Coelho, Ana Luísa; Campinho, Marco António; Teotónio Fernandes, Mónica AlexandraGlioblastoma (GBM) is a relatively rare but highly aggressive form of brain cancer characterized by rapid growth, invasiveness, and resistance to standard therapies. Despite significant progress in understanding its molecular and cellular mechanisms, GBM remains one of the most challenging cancers to treat due to its high heterogeneity and complex tumor microenvironment. To address these obstacles, researchers have employed a range of models, including in vitro cell cultures and in vivo animal models, but these often fail to replicate the complexity of GBM. As a result, there has been a growing focus on refining these models by incorporating human-origin cells, along with advanced genetic techniques and stem cell-based bioengineering approaches. In this context, a variety of GBM models based on brain organoids were developed and confirmed to be clinically relevant and are contributing to the advancement of GBM research at the preclinical level. This review explores the preparation and use of brain organoid-based models to deepen our understanding of GBM biology and to explore novel therapeutic approaches. These innovative models hold significant promise for improving our ability to study this deadly cancer and for advancing the development of more effective treatments.
- Annexin A2 regulates AKT upon H2O2-dependent signaling activation in cancer cellsPublication . Castaldo, Stéphanie Anais; Ajime, Tom; Serrão Fernandes, Lina Gisela; Anastácio, Fábio; Rosa, Joana Teixeira; Giacomantonio, Carman Anthony; Howarth, Alison; Hill, Richard; Madureira, PatriciaHydrogen peroxide (H2O2) is a main second messenger in oncogenic signaling networks including the Ras and the growth factor receptor pathways. This is achieved predominantly through the oxidation of redox-sensitive cysteine (Cys) residues in proteins resulting in changes to their structure and function. We previously identified annexin A2 (ANXA2) as a redox regulatory protein that plays an important cellular role during oxidative stress and also promoting tumorigenesis. Here we investigated the role of ANXA2 in the regulation of H2O2-dependent signaling that drives tumor progression. We show that depletion of ANXA2 leads to the enhanced activation of AKT following either EGF/EGFR stimulation or oncogenic Ras transformation. The phosphatase and tensin homologue (PTEN) protein negatively regulates the PI3K/AKT pathway. We demonstrate that ANXA2 via its reactive Cys-8 residue, binds to PTEN and that the co-expression of PTEN and ANXA2, but not ANXA2 Cys-8-Ala mutant, inhibits AKT phosphorylation on Ser 473. These results indicate that ANXA2 is important for PTEN regulation within the PI3K/AKT signaling cascade. Furthermore, we also reveal that ANXA2 inversely regulates the expression of the peroxidase, peroxiredoxin 2, in a reactive oxygen species dependent manner.
- Antimicrobial and antioxidant activities of natural compounds: enhance the safety and quality of foodPublication . Faleiro, Maria Leonor; Miguel, Maria da GraçaNature has offered us a tremendous diversity of natural compounds, for which antimicrobial and antioxidant properties have been intensively explored and nowadays are plenty recognized. During the last decades both the antimicrobial action of natural compounds (preventing and limiting microbial growth) and their antioxidant properties (reducing the oxidation of fats and limiting the ripening and browning of fruit and vegetables after harvesting) have been intensively investigated, particularly in the food packaging sector, evidencing that they may represent an effective eco-friendly approach to enhance the safety and quality of food products, without an environmentally deleterious impact.
- Association of epigenetic age and outcome in critically Ill patientsPublication . Sharma-Oates, Archana; Sullivan, Jack; Pestana, Daniel; Santos, Claudia C. dos; Binnie, Alexandra; Lord, Janet M.OBJECTIVES: DNA methylation can be used to determine an individual’s biological age, as opposed to chronological age, an indicator of underlying health status. This study aimed to assess epigenetic age in critically ill patients with and without sepsis to determine if higher epigenetic age is associated with admission diagnosis or mortality. DESIGN: Secondary analysis of whole blood DNA methylation data generated from a nested case–control study of critically ill septic and nonseptic patients. SETTING: Four tertiary care hospitals in Canada. INTERVENTIONS: None. PATIENTS: Critically ill patients with and without sepsis. MEASUREMENTS AND MAIN RESULTS: Epigenetic age was derived from DNA methylation data using the Hannum and PhenoAge algorithms and deviation from the patient’s chronological age in years was determined. Of the 66 patients with sepsis, 34 were male (51.5%), the mean age was 65.03 years and 25 patients (37.8%) died before discharge. Of the 68 nonseptic patients, 47 were male (69.1%), the mean age was 64.92 years and 25 (36.7%) died before discharge. Epigenetic age calculated using the PhenoAge algorithm showed a significant age acceleration of 4.97 years in septic patients (p = 0.045), but no significant acceleration in nonseptic patients. Epigenetic age calculated using the Hannum algorithm showed no significant acceleration in the septic or nonseptic patients. Similarly, in the combined septic and nonseptic cohorts, nonsurvivors showed an epigenetic age acceleration of 7.62 years (p = 0.004) using the PhenoAge algorithm while survivors showed no significant age acceleration. Survivor status was not associated with age acceleration using the Hannum algorithm.
- Autoantibodies against myelin oligodendrocyte glycoprotein in a subgroup of patients with psychotic symptomsPublication . Burgt, Nikita A. van de; Kulsvehagen, Laila; Mané-Damas, Marina; Lutz, Luc; Lecourt, Anne-Catherine; Monserrat, Clara; Vinke, Anita M.; Küçükali, Cem İ.; Zong, Shenghua; Hoffmann, Carolin; González-Vioque, Emiliano; Arango, Celso; Leibold, Nicole K.; Losen, Mario; Molenaar, Peter C.; Tüzün, Erdem; Beveren, Nico J. M. van; Mané, Anna; Rouhl, Rob P. W.; Amelsvoort, Therese A. M. J. van; Pröbstel, Anne-Katrin; Martinez-Martinez, PilarThe presence of autoantibodies against myelin oligodendrocyte glycoprotein (MOG) is a hallmark of MOG antibody-associated disease (MOGAD), a recently defined demyelinating disease entity presenting with core clinical features of optic neuritis, myelitis, and acute disseminated encephalomyelitis. Although MOG antibodies have also been described in a small number of patients with other conditions, including mental disorders, their prevalence and clinical specificity in patients with isolated psychotic symptoms remain unclear. Here, we screened sera from 262 patients with at least one psychotic episode and 166 control subjects for the presence of MOG antibodies of the immunoglobulin G (IgG) isotype with a live cell-based assay. Serum reactivity to additional antigens was assessed by immunohistochemistry. Four patients, representing 1.5% of the patient cohort, and one control individual, representing. 0.6% of the healthy control cohort, were seropositive for MOG-IgG antibodies. Of the four MOG-IgG seropositive patients, three experienced visual hallucinations. Overall, MOG antibodies were detected at a low frequency in patients with psychotic episodes. While we cannot exclude the possibility of false-positive results or seroconversion due to secondary myelin damage, the association with visual hallucinations in three out of four MOG-IgG seropositive patients may point toward an underlying autoimmune etiology.
- Automedicação: hábitos durante um período de pandemia - estudo transversalPublication . Espírito-Santo, Margarida; Estêvão, M. Dulce; Campos, EricaA automedicação é uma prática muito comum e a pandemia de COVID-19 poderá ter criado condições para haver um maior recurso às farmácias comunitárias, particularmente em situações de doença ligeira. Esse estudo teve como objetivo analisar os hábitos de automedicação de uma amostra da população Portuguesa durante o período inicial da pandemia (março-novembro 2020), identificar os medicamentos não sujeitos a receita médica (MNSRM) e suplementos alimentares mais consumidos, bem como as situações que levaram os indivíduos a recorrer à automedicação e a informação sobre estes produtos. Foi realizado um estudo transversal, observacional, através da aplicação de um questionário com recurso a uma plataforma da internet, durante o mês de dezembro 2020. Os dados foram obtidos de forma anónima, e analisados com o programa IBM SPSS v26. A amostra em análise era composta por 170 indivíduos, tendo-se verificado que a pandemia parece não ter afetado a frequência de ida à farmácia. As situações que mais levaram as pessoas a recorrer à automedicação foram dores de cabeça e dores musculares. Os medicamentos mais utilizados neste período pelos participantes neste estudo foram os analgésicos e os anti-inflamatórios. Apesar de todas as restrições impostas pela situação pandémica, parece não ter havido um impacto negativo no recurso às farmácias comunitárias, nem um aumento significativo da prática de automedicação. Foi também assinalado o papel relevante dos profissionais de Farmácia, em particular nas situações de automedicação, como fonte de informação sobre o uso dos medicamentos e dos suplementos alimentares.
- Autophagy in Spinocerebellar Ataxia Type 3: From pathogenesis to therapeuticsPublication . Paulino, Rodrigo; Nóbrega, ClévioMachado–Joseph disease (MJD) or spinocerebellar ataxia 3 (SCA3) is a rare, inherited, monogenic, neurodegenerative disease, and the most common SCA worldwide. MJD/SCA3 causative mutation is an abnormal expansion of the triplet CAG at exon 10 within the ATXN3 gene. The gene encodes for ataxin-3, which is a deubiquitinating protein that is also involved in transcriptional regulation. In normal conditions, the ataxin-3 protein polyglutamine stretch has between 13 and 49 glutamines. However, in MJD/SCA3 patients, the size of the stretch increases from 55 to 87, contributing to abnormal protein conformation, insolubility, and aggregation. The formation of aggregates, which is a hallmark of MJD/SCA3, compromises different cell pathways, leading to an impairment of cell clearance mechanisms, such as autophagy. MJD/SCA3 patients display several signals and symptoms in which the most prominent is ataxia. Neuropathologically, the regions most affected are the cerebellum and the pons. Currently, there are no disease-modifying therapies, and patients rely only on supportive and symptomatic treatments. Due to these facts, there is a huge research effort to develop therapeutic strategies for this incurable disease. This review aims to bring together current state-of-the-art strategies regarding the autophagy pathway in MJD/SCA3, focusing on evidence for its impairment in the disease context and, importantly, its targeting for the development of pharmacological and gene-based therapies.