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Generation of a novel Cockayne syndrome B neuronal culture model from patient-derived induced pluripotent stem cells
No full textCockayne syndrome type B (CSB) is a rare genetic, multisystem disorder, which results from accumulation of DNA damage that arises when the associated gene, ERCC6, is dysfunctional. This leads to premature aging and neurodegeneration. Studies on CSB pathophysiology are lacking, and pre-clinical research of potential therapeutic strategies is nonexistent. Patients with CSB are left without any chance of disease cure or delay, experiencing premature death. Patient-derived induced pluripotent stem cells (iPSCs) offer a powerful tool to investigate disease mechanisms while generating possibilities for treatment. As a result, our goal was to generate iPSCs from the fibroblasts of CSB patient, as an in vitro model, and differentiate them into neural cell cultures that exhibit CSB-related neuropathological alterations. To achieve this goal, human patient fibroblasts were reprogramed into CSB-iPSCs with the CytoTune iPS 2.0 Sendai Reprogramming Kit. CSB-iPSCs and fibroblasts genetic profile analysis confirmed relatedness between cell lines. The ERCC6 gene was sequenced demonstrating to have the expected mutation, and Western blot analysis further confirmed the presence of a pathogenic mutation. PCR showed that CSB-iPSCs are free of reprograming virus at passage 10 and cultured cells did not contain mycoplasma contamination. Through immunohistochemistry and flow cytometry, CSB-iPSCs demonstrated to express pluripotency markers and capacity to differentiate into the three germ layers. CSB fibroblasts displayed an accumulation of dysfunctional mitochondria, and their DNA repair capacity was affected, upon UV light exposure, as observed through flow cytometry and immunocytochemistry, respectively. This suggests that CSB cells have a dysfunctional transcription-coupled nucleotide excision repair (TC-NER) and mtDNA repair. CSB-iPSCs were successfully differentiated into neurons and CSB-Neurons appeared to have longer neuronal prolongations that neurons derived from a healthy donor, indicating premature maturation. Our study suggests that the in vitro CSB model generated can help understand this disorder and contribute to the pre-clinical testing of disease-modifying therapies.As síndromes progeroides humanas são um conjunto de doenças genéticas raras caracterizadas pelo envelhecimento precoce. Embora a compreensão das causas subjacentes a algumas destas doenças tenha sido benéfica no desenvolvimento de terapias, isso não é válido para todas estas condições. A síndrome de Cockayne tipo B (CSB) é uma doença rara, multisistémica, com hereditariedade autossómica recessiva, que resulta do acumular de danos no ADN que surgem quando o gene associado, ERCC6, está disfuncional. Isto acaba por induzir envelhecimento precoce e neurodegeneração. Para além disto, os sintomas desta doença incluem microcefalia pós-natal, atraso severo do crescimento, hipersensibilidade à luz ultravioleta (UV), anormalidades músculo-esqueléticas, deterioração dentário, perda de audição e problemas oculares. No entanto, pneumonia, outras complicações respiratórias e falha renal são as causas mais comuns de morte nestes doentes. Existem três tipos diferentes de síndrome de Cockayne (CS), nomeadamente: (i) tipo I (CS I), a forma clássica, em que os sintomas se manifestam nos primeiros dois anos de vida dos doentes, que têm uma esperança média de vida de 16 anos; (ii) tipo II (CS II), a forma mais severa, com um fenótipo caracterizado por se manifestar antes do nascimento, esperança média de vida muito curta (5/6 anos) e problemas neurológicos severos; e (iii) tipo III (CS III), correspondente a um fenótipo moderado, em que os doentes possuem uma esperança média de vida de 30 anos. Os doentes com mutações no gene ERCC6 normalmente estão mais associados a CS II. Estudos sobre a fisiopatologia de CSB são notavelmente escassos, e investigação pré-clínica de possíveis estratégias terapêuticas é virtualmente inexistente. Os doentes com CSB ficam, assim, sem qualquer hipótese de cura ou atraso da doença, sofrendo uma morte prematura entre os 5 e os 30 anos
A survey on ISO 9001 decertified companies: the three stages leading to withdrawal
No full textThis study investigates the three main stages of the ISO 9001 certification process (implementation, maintenance, and withdrawal) from the perspective of decertified firms. The research employs a descriptive and inductive survey methodology, drawing insights from a literature review and the analysis of primary data obtained from a sample of decertified organisations. Results suggest that the decertification is triggered during the pre-certification stage, where these firms overemphasise external motivations to the detriment of internal ones. Additionally, this study finds that, in the maintenance stage, these firms are unable to commit to continuous improvement. The interplay of external motivations, the lack of internalisation and continuous improvement, and the nature of benefits gained by these entities ultimately leads to certification withdrawal. Furthermore, the paper highlights that the consequences of decertification vary: most firms report no negative impact on their performance, but
some report a negative impact, which seems to result from even stronger external motivations. This is the first descriptive (and inductive) study to address decertification from the dual perspective of the whole certification process and of the decertified firms, adding to the scarce research on decertification by providing a comprehensive overview of this phenomenon and identifying a holistic explanation for the withdrawal.info:eu-repo/semantics/publishedVersio
Biodegradation of ibuprofen and fluoxetine by bacterial strains isolated from environmental samples and identification of candidate catabolic genes
No full textPharmaceuticals are commonly found in surface waters due to high global demand. Conventional wastewater treatment plants don’t remove them completely being a major source of these compounds, which pose a risk to the environment and human health despite their low concentrations. The objective of the present investigation was to isolate bacteria from environmental and wastewater samples from the Algarve area potentially exposed to recalcitrant contaminants (aromatic compounds), capable of degrading pharmaceuticals. Ibuprofen (IBU) and fluoxetine (FLX), two of the most common drugs found in effluents worldwide, were the targets. Twenty bacterial strains were isolated using enrichment cultures. However, only three strains (TIBU2.1, LOI1.1 and LOI1.2) showed the ability to degrade IBU, and two (LOFLX1.1 and LOFLX1.3) FLX. The drug concentration was monitored by HPLC, as well as the presence of IBU metabolites eventually formed during biodegradation. In addition, two bacterial strains (Mycolicibacterium aubagnense HPB1.1 and Micrococcus yunnanensis TJTP4), previously isolated for other pharmaceuticals, were investigated in this work. Klebsiella pneumoniae TIBU2.1 and M. yunnanensis TJTP4 exhibited complete degradation of IBU after 15 and 14 days, respectively, while M. aubagnense HPB1.1 was also able to degrade 60.2% ± 0.4 of IBU after 21 days. Additionally, the complete genomes of these three bacterial strains were sequenced to conduct a preliminary analysis of candidate genes involved in the degradation pathway of IBU. Catabolic enzymes reported in databases and literature for IBU biodegradation were used to search for similar proteins translated by the obtained genome sequences. These in silico analyses on the bacterial genomes showed similarities with most of the reported proteins. This work provides useful genetic information for the development of bioaugmentation techniques and reports new bacteria for bioremediation processes transforming IBU into less toxic metabolic compounds.Os produtos farmacêuticos constituem um mercado em crescimento, altamente procurado ano após ano, o que faz com que estes compostos sejam continuamente detetados nos efluentes e nas águas superficiais. Apesar desses compostos poderem chegar ao ambiente através de diferentes fontes, as estações de tratamento de águas residuais (ETARs) são incapazes de os eliminar completamente, sendo por isso a maior fonte de contaminação ambiental destes poluentes. Foi demonstrado que, apesar das baixas concentrações de descarga presentes nas águas residuais (de ng L-1 a μg L-1), a sua presença nos ecossistemas representa um risco para o meio ambiente e para a saúde humana. A utilização de processos de bioaumentação e bioestimulação apresentam-se como técnicas promissoras para a eliminação desses contaminantes. Para alcançar esse objetivo é fundamental isolar bactérias que possuam a capacidade de degradação dessas substâncias. Além disso, o entendimento da via de degradação e dos genes envolvidos pode ser útil no desenvolvimento de ferramentas a ser utilizadas na bioaumentação de bactérias, ou bioaumentação genética por transferência horizontal de genes de enzimas catabólicas em plasmídeos. Assim, o objetivo principal deste trabalho, a fim de melhorar os processos de tratamento de águas residuais, foi isolar estirpes bacterianas com a capacidade de degradar o anti-inflamatório monocíclico não esteroidal ibuprofeno (IBU) e o antidepressivo fluoxetina (FLX), dois medicamentos comumente encontrados nos efluentes de águas residuais que acabam no mar. Estas bactérias foram isoladas de amostras de sedimentos ambientais de diferentes pontos da região do Algarve, potencialmente afetados por contaminantes recalcitrantes como a gasolina e óleos lubrificantes e também de águas residuais de lagar de azeite – águas ruças - e seus sedimentos, uma vez que estes contêm compostos com aneis aromáticos, tal como o IBU e a FLX. Para selecionar bactérias potencialmente degradadoras foram feitos enriquecimentos em solução aquosa com meio mineral salino (MSM) suplementado com altas concentrações de IBU e FLX (100 mg L-1), a partir dos quais foram isoladas em placa um total de 20 estirpes bacterianas (11 para IBU e 9 para FLX) com diferenças morfológicas entre elas. Dessas apenas 3 (TIBU2.1, LOI1.1 e LOI1.2) foram capazes de degradar IBU e 2 (LOFLX1.1 e LOFLX1.3) FLX, em solução aquosa. Para além dos novos isolamentos obtidos neste trabalho, também foi avaliado o potencial de degradação de duas bactérias previamente isoladas para outros fármacos no laboratório de Tecnologias Ambientais do CCMAR onde decorreu o trabalho: Mycolicibacterium aubagnense HPB1.1 e Micrococcus yunannensis TJPT4.(...
New TiO2-Ag/BEA composites with dual Ag-functionalization for specific adsorption and catalytic sites. Synergism between phases in the ethylene removal for climateric fruit conservation
No full textA new series of TiO2-Ag/BEA composites was specifically designed for use in filter/photo-reactors intercalated in air recirculation circuits in storage facilities for climacteric fruits. The sol-gel procedure for TiO2 deposition was combined with ionic exchange (IE) or incipient wet impregnation (IWI) techniques for Ag doping, with the proportions of both fractions also varying. The prepared materials were thoroughly characterized in terms of their porous texture, chemical composition, crystalline structure, and Ag dispersion, among other properties. Dynamic ethylene adsorption was recorded in the dark. After saturation, ethylene photooxidation was analyzed under UV or UVA-visible light, with varying contact times, flow rates, and concentrations, and with or without humidity present. The maximum ethylene adsorption capacity (361 μmol g− 1 ) corresponds to the sample with the highest Ag content (5 wt%), added by IE, while the best photocatalytic performance is obtained for samples doped by IWI. The performance of the samples was found to be correlated with their physicochemical properties and was specifically determined by the nature and dispersion of the silver species in the composites. Total ethylene photooxidation is achieved even under UV–Vis radiation; the reaction develops selectively to CO2 in all cases, despite the strong negative effect of humidity on the formation of more active HO• radicals. The high adsorption capacity and effective photooxidation of ethylene enable control of this maturation hormone below the established limits.N/
Gamification on mathematics engagement and motivation in secondary school and higher education: a systematic review and meta-analysis
No full textThis systematic review and meta-analysis examined the effects of gamification on students’ motivation and engagement in mathematics at the secondary and higher education levels. A literature search (April 2025) followed by an updated search (November 2025) across ten databases identified 45 studies for qualitative synthesis and 11 for meta-analysis. The review followed PRISMA 2020 guidelines with a pre-registered protocol, and study quality was appraised with the Mixed Methods Appraisal Tool. Meta-analytic results using a three-level Correlated and Hierarchical Effects model with robust variance estimation showed a significant small-to-moderate positive effect on motivation (g = .383, 95% CI [.11, .66], p = .0218). Motivation was assessed more consistently than engagement that could not be included in the meta-analysis due to the lack of validated measures. The systematic review indicates that gamification supports motivation and engagement, with only four studies reporting negative effects. Most interventions used digital platforms (e.g., Kahoot!; Classcraft) and common game elements such as points, leaderboards and instant feedback. Overall, gamification appears promising for enhancing motivation and engagement in mathematics when designs are aligned with students’ needs, balancing competition with mastery and cooperation. Therefore, educators should limit excessive competition and prioritize personal progress and cooperative tasks that foster social interaction. Future studies should employ validated measures, larger samples, and examine both motivation and engagement to strengthen the evidence base and guide effective implementation in education.2024.00502.B
Transcriptomic insights into metabolic reprogramming and exopolysaccharide synthesis in porphyridium purpureum under gradual nitrogen deprivation
No full textPorphyridium species are known red microalgae for producing valuable bioactive compounds such as sulfated exopolysaccharides (EPS) with diverse industrial biomedical applications due to their functional and rheological properties. Recent studies have investigated how abiotic stresses, particularly nitrogen deprivation, affect Porphyridium’s metabolic regulation and EPS production through transcriptomic analysis. Still, the mechanisms governing EPS biosynthesis and the involvement of carbohydrate-activated enzymes (CAZymes) remain poorly understood. This study investigated the progressive effects of nitrate consumption on the unicellular red alga, P. purpureum, by integrating physiological, biochemical, and transcriptomic analyses through RNA-Seq, further validated by RT-qPCR. P. purpureum displayed a gradual, phase-dependent metabolic response to progressive nitrogen stress. EPS release coincided with the decline in nitrate uptake, linking nitrogen availability to carbon redirection towards polysaccharide secretion. Transcriptomic data revealed global metabolic downregulation with targeted upregulation of stress-responsive, carbohydrate catabolic, and nucleotide–sugar synthesis pathways, including the upregulation of CAZyme families GT4, GT8, and GT77. Our results give insights into the coordinated nitrogen and carbon metabolic regulation underlying polysaccharide biosynthesis, while opening future perspectives on enzyme compartmentalization and regulatory flux distribution under nitrogen stress in P. purpureum.ANR- 20-DFRI-000
Efficacy of slow sand filtration enriched with trichoderma atroviride in the control of fusarium oxysporum in soilless cultivation systems
No full textOn a planet intending to move toward carbon neutrality while ensuring food security, maximizing water and nutrient use efficiency in agriculture is essential. Soilless cultivation offers a promising solution for food production, yet in substrate-based systems, excess nutrient solution (drainage) is often discarded to maintain phytosanitary safety, resulting in considerable water and nutrient waste. Reusing this drainage requires disinfection to eliminate pathogens. Among available methods, slow sand filtration (SSF) is ecological, economical, and simple, showing strong biological control potential, though not always fully effective against Fusarium oxysporum. Trichoderma atroviride, an antagonistic fungus, may enhance SSF performance. Its antagonistic capacity was evaluated in vitro via direct confrontation assays and in vivo using a closed-loop soilless cucumber cultivation system with eight treatment combinations of SSF, T. atroviride, and F. oxysporum. SSF reduced F. oxysporum incidence by approximately 48%, T. atroviride in irrigation by 44%, and SSF enriched with T. atroviride reached 58% disease incidence reduction, though this increase was not statistically significant. These results confirm that both SSF and T. atroviride can partially suppress F. oxysporum, but further optimization is needed for consistent and complete pathogen control.UID/05183/202
A new dating for the origins of tourism: evidence from Göbeklitepe, Türkiye
No full textGöbeklitepe, built around 12,000 years ago and recognized as the world’s earliest monumental ritual centre, has the potential to reshape debates on the origins of tourism. Challenging the mainstream view that situates tourism solely in modern times, this study examines whether activities at Göbeklitepe align with the four fundamental principles of tourism – temporary stay, motivation, economic exchange, and socio-cultural interaction. A systematic literature review was conducted, synthesizing 68 studies and comparing archaeological findings with tourism theory. Results indicate that faith-based motivations, periodic gatherings, and temporary visits created economic and socio-cultural dynamics resembling tourism practices, suggesting Göbeklitepe may be interpreted as a form of proto-tourism destination
Assessing the impact of gram-negative bacteria on the common octopus, in relation to rising sea temperature: a study of total protein concentration and hemolysis activity in hemolymph
No full textFish farming may pose a risk to adjacent octopus farms due to pathogen transmission. Moreover, the immune defense mechanisms of cephalopods are still not fully understood. This study aimed to determine changes in total protein concentration and hemolysis activity of Octopus vulgaris hemolymph, after intramuscular (IM) or intravenous (IV) challenges with aquaculture fish pathogens (either Photobacterium damselae subsp. piscicida or damselae or Vibrio alginolyticus or anguillarum O1) at two temperatures (21 ± 0.5 ℃ and 24 ± 0.5 ℃). Results showed that Octopus vulgaris exhibited a mean total protein concentration of 173.93 ± 69.37 mg/mL across all experimental conditions, markedly exceeding values reported for other mollusks, such as the bivalves Chamelea gallina (0.75–1.66 mg/mL) and Mytilus galloprovincialis (0.59–1.60 mg/mL). Patterns of total protein concentration, related to the genera of the pathogen used for the challenges, were observed. Four-way ANOVA revealed significant main effects of bacterium (F(3, 144) = 54.360, p < 0.001) and temperature (F(1, 144) = 10.014, p = 0.002) on total protein, along with multiple significant interaction effects, including bacterium × temperature, route × time, and bacterium × route × temperature × time (all p < 0.001). Hemolysis remained at low levels across both experimental temperatures, challenge routes, and pathogens, not exceeding 25 % in any case. Values above 15 % and up to 20 % were recorded in specific conditions, such as Photobacterium damselae subsp. damselae at 24 ± 0.5 ◦C on Day 3 in CIM-, IM-, and IV- control and challenged groups respectivelly; V. alginolyticus at 24 ± 0.5 ◦C on Day 3 in IM-challenged groups; and Vibrio anguillarum O1 at 21 ± 0.5 ◦C on Day 3 and Day 7 in IM-challenged groups. ANOVA for hemolytic activity showed significant main effects of bacterium (F(3, 144) = 22.032, p < 0.001) and temperature (F(1, 144) = 4.083, p = 0.045), with multiple significant interactions, including bacterium × temperature, route × time, and bacterium × route × temperature × time (all p < 0.001). These results indicate that the route of challenge may play a major role in hemolysis activity, with temperature and time post-challenge also exerting significant effects, possibly through a complex synergistic interaction. Our results may assist in elucidating common octopus defense mechanisms against common fish pathogens and provide important information to the scientific community and the marine aquaculture sector
Safe applications of ozone in tropical marine RAS: determining impacts of elevated total residual oxidants (TRO) on Stylophora pistillata and Xenia sp. holobionts
No full textOzone-aided treatment of seawater creates secondary oxidants, which can be toxic for aquaculture animals. We aimed to define safe limits of ozonation-derived total residual oxidants (TRO) for Stylophora pistillata and Xenia sp. by conducting a 96 h acute toxicity experiment. In a chronic exposure experiment we then determined the impacts of three sub-lethal levels of TRO on animal health over four weeks by monitoring respiration, net photosynthesis, photosynthetic efficiency, and three oxidative stress biomarkers (CAT, SOD, LPO). We further documented the changes in coral surface microbiomes exposed to elevated TRO with 16S rRNA amplicon gene sequence analysis. We showed that Xenia sp. is more susceptible to elevated TRO, with first mortalities occurring within 24 h at 0.188 mg L-1 and higher. In Stylophora, mortalities were observable within 24 h at 1.272 mg L− 1 and after 72 h at 0.353 mg L− 1 TRO. Sub-lethal TRO levels caused higher respiration and lower photosynthetic efficiency in Xenia, and increased catalase activity by 29–42 % in Stylophora and by 38–45 % in Xenia, while not impacting lipid peroxidation or superoxide dismutase activity. Microbiomes displayed TRO-induced changes in both species, with a decline in Saprospiraceae as a potential indicator for ozone-inflicted mucus layer degradation. Vibrionaceae fully disappeared from Stylophora pistillata microbiomes after 26 days of exposure to 0.131 mg L-1 TRO, suggesting ozonation as a potential tool to treat pathogens in coral aquaculture. Our study represents the first analysis of ozonation-induced impacts on coral holobionts, thereby providing a guideline for the safe application of ozone in coral cultivation.CEECINST/00114/201