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- Development of a decellularized extracelular matrix from porcine aorta for heart valve applications in the Ross procedurePublication . Reis, Mariana S.; Rosadas, Marta; Ho, Chou I.; Costa, João; Vervenne, Thibault; Oliveira, Ana L.; Ribeiro, Viviana P.; Mignon, ArnCardiovascular diseases are the leading cause of adult mortality worldwide, according to the WHO [1]. An important surgical approach for treating diseased aortic valves is the Ross procedure, in which the affected aortic valve is replaced with an autograft from the patient’s own pulmonary valve. The main concern about this procedure is linked to wall dilatation, which can lead to valve leakage and reoperation. Dilatation occurs due to the fivefold increase in blood pressure when transitioning from pulmonary to aortic conditions. Current solutions rely on permanet and stiff synthetic materials to provide structural support, however, these lack biological functionality. Our approach aim to incorporate a decellularized extracellular matrix (dECM) in a semi-permanent textile wrapped around the autograft promoting benign biological adaptation. The decellularization process by removing cellular components, reduces the risk of inflammatory responses and immune rejection. Moreover, essential ECM components that regulate cellular behavior are mantained, which is crucial for effective decellularization outcomes [2]. This study is focused in the development and optimization of an efficient decellularization protocol for obtaining dECM from porcine aorta with mild effects on ECM components preservation. Decellularization of the porcine aortic tissue was performed using a detergent and enzymatic-based protocol combined with supercritical CO₂ (scCO₂). Additional steps of sonication, agitation, washing and freeze-thaw were performed to enhance decellularization efficiency. Graphic A shows a significant decrease in the DNA content after optimized decellularization processing, indicating the removal of approximatly 85% of the DNA from the native tissue, and suggest an effective reduction of potential immunogenic components. Further characterization of ECM components (i.e. glycosaminoglycans, total collagen and elastin) is required to evaluate its preservation and the biological potencial of the dECM when integrated in the Ross processure. To do so, aorta dECM powder will be combined with polycaprolactone and elastin and processed through electrospinning used to create a tubular device to enhance bio-mechanocompatibility, further improving current external supports for the Ross procedure and enhancing its general clinical outcomes. Since this support is biodegradable, it allows the new valve to take over the required strength. The dECM specifically offers essential biochemical cues to promote tissue integration and enable long-term functional repair after the Ross procedure.
- Development of a decellularized extracelular matrix from porcine aorta for heart valve applications in the Ross procedurePublication . Reis, Mariana S.; Rosadas, Marta; Ho, Chou I.; Sousa, Teresa; Pazmino, Carlos; Costa, João; Vervenne, Thibault; Oliveira, Ana L.; Ribeiro, Viviana P.; Mignon, ArnCardiovascular diseases are the leading cause of adult mortality worldwide, according to the World Health Organization [1]. An important surgical approach for treating diseased aortic valves is the Ross procedure, in whic the affected aortic valve is replaced with an autograft from the patient’s own pulmonary valve.
- Detergent-free supercritical CO2–assisted protocol for the production of sustainable and highly preserved decellularized porcine meniscus for orthopedic applicationsPublication . Ho, Chou I.; Rodrigues, Francisco A. P.; Reis, Mariana S.; Ribeiro, Viviana P.; Oliveira, Ana Leite; Costa, João B.Introduction & Objectives Meniscal injuries occur approximately 66 to 70 per 100,000 individuals annually (Fig. 1), potentially leading to the development of osteoarthritis (OA) or other degenerative cartilage disease in 10 to 20 years. One of the conventional treatments is meniscal allograft transplantation. However, its limitations constrain its comprehensive application in the healthcare system.
- Coaxial 3D printing: synergistic approach of natural and synthetic biomaterials for knee meniscus replacementPublication . Rodrigues, Francisco A. P.; Araújo, Marco; Granja, Pedro L.; Oliveira, Ana Leite; Costa, João B.
- Exploring the bioavailability of phenolic compounds through in vitro simulated gastrointestinal digestion: INFOGESTPublication . Pais, Adriana C. S.; Coscueta, Ezequiel R.; Pintado, Maria Manuela; Silvestre, Armando J. D.; Santos, Sónia A. O.Conclusions: Studied phenolic compounds did not undergo enzymatic digestion after INFOGEST, as we did not detect any resultant metabolites. Bioaccessibility percentages determined after the intestinal digestion phase showed that most of the studied phenolic compounds were about 50% bioaccessible. Absorption rates of all studied phenolic compounds were high (> 80%), suggesting that they can be absorbed into the systemic circulation or follow to the colon, where gut microbiota may metabolize them. Solubility of phenolic compounds could limit their bioavailability, as QUE and EA, demonstrated lower bioaccessibility along the simulated gastrointestinal tract due to their low solubility in water.
- Evaluation of oat syrup, from oat beverage by-products for sugar reduction in food productsPublication . Gomes, A.; Gonçalves, J.; Paupério, A.; Alves, V.; Pintado, M.The agro-food industry is responsible for the annual production of millions of tons of food waste. At the same time, consumers are more informed and conscious about their food choices, seeking convenient, healthy, and sustainable products. In response, the industry proposes to provide natural products with limited additives, while still meeting sensory, nutritional, and safety requirements. Oats (Avena sativa L.) are the sixth largest cereal crop worldwide, becoming increasingly popular with health-conscious consumers because of their exceptional nutritional profile. They are particularly rich in dietary fibre, phytochemicals and essential nutrients such as vitamins and minerals. In this context, oats are chosen by consumers who prioritize health-promoting properties, as well as sensory appeal. This study aimed to transform an oat drink by-product into a new added-value product, that can be used as a sugar-replacement ingredient in food products. To release the by-product sugars, different hydrolysis processes were carried out. Thermal hydrolysis using water was carried out with proportions of 4:10 and 1:1 (residue: solvent). From this by-product hydrolysis, the supernatant residue was separated by centrifugation (10,000rpm, 10min) and the concentrations of sugars (mono and disaccharides) were analysed from the liquid fraction using the HPLC. The Brix for the obtained supernatant was also determined, as well as the sweetness index as a function of sucrose. Aqueous thermal hydrolysis (1:1 ratio, temperature of 121 ºC for 15 minutes, and pressure of 1 atm) was found to be the most effective process, resulting in fibres with good sweetening power. According to sugars HPLC profiles, the resulting supernatant liquid exhibited a sucrose concentration of 72.35 ± 8.13 g, glucose concentration of 56.59 ± 6.23 g, and fructose concentration of 2.89 ± 0.05 g per 100 g of sample, with a sweetness index of 1.24. The liquid fraction was then concentrated to produce an oat syrup with a Brix value of approximately 67º, indicating high levels of dissolved solids. In conclusion, this oat syrup exhibits promising sweetening properties and could potentially serve as a substitute for sucrose in certain food products, contributing to reducing food waste and promoting further a circular economy.
- Dietary carotenoids and their modulation of intestinal microbiotaPublication . Rocha, Helena R.; Gomes, Ana M.; Pintado, Manuela E.; Coelho, Marta C.Noncommunicable diseases (NCDs) are a major global health concern, causing 41 million deaths annually. Unhealthy dietary behaviours are closely linked to NCDs, the reason why nutrition and health organizations emphasize the importance of consuming fruits and vegetables regularly. Being the most common lipid-soluble phytochemicals in the human diet, carotenoids and their metabolites have been linked to various health benefits. The effectiveness of carotenoids is influenced by multiple factors, with the intestinal microbiota (IM) playing a pivotal role in their absorption and metabolism. Dietary choices significantly impact the IM composition, affecting microbial species' proliferation, which can have both protective and detrimental effects. Moreover, IM generates metabolites that enter the bloodstream, influencing the host's IM composition and function, and playing roles in certain diseases. The present work aimed to explore the interaction between carotenoids and the IM. An in vitro gastrointestinal digestion simulation was conducted with three carotenoids (β-carotene, lutein, and lycopene), a mixture of these pigments, and the algae Osmundea pinnatifida. After, digested samples were tested on human faeces to assess their impact on gut microbiota dynamics and metabolic activity. At the phylum level, the intestinal microbiota in all tested groups primarily consisted of Bacteroidota, Bacillota, Pseudomonadota, and Actinomycetota, consistent with prior research. In general, carotenoids promoted the growth of Lachnospiraceae family bacteria while reducing Lactobacillus, Enterococcus, Streptococcus, and Bifidobacterium populations. These bacteria used glucose as a carbon source and produced organic acids like succinic, acetic, butyric, propionic, and malic acids. Functionally, all groups exhibited antioxidant and anti-diabetic activity, with lutein and the Mix group showing the highest levels, respectively. None of the samples displayed mutagenicity, and some even exhibited an anti- mutagenic effect. Importantly, all samples with lower carotenoid concentrations were non-cytotoxic. This study reveals the complex relationship between carotenoids and the gut microbiota, underscoring their potential to positively influence human health.
- Dietary carotenoids and their modulation of intestinal microbiotaPublication . Rocha, Helena R.; Gomes, Ana M.; Pintado, Manuela E.; Coelho, Marta C.Introduction: Annually, 41 million deaths are linked to Non-Communicable Diseases (NCDs), often due to poor diets, emphasizing the importance of health-recommended fruits and vegetables. Carotenoids, lipid-soluble compounds found in plants, bacteria, microalgae, and fungi, offer antioxidant protection and promote cardiovascular health and anti-inflammatory effects. The efficiency of carotenoids is influenced by the intestinal microbiota (IM), which plays a crucial role in their absorption and metabolism. Dietary changes can impact the IM, affecting microbial proliferation and the production of metabolites crucial in diseases. Despite their significance, there's a research gap in understanding carotenoids' colon metabolism and interactions, necessitating further exploration. Introduction The study aimed to evaluate the effects of digested beta(β)-carotene, lutein, and lycopene, a mixture of these pigments, and Osmundea pinnatifida solutions on the metabolic and population dynamics of the intestinal microbiota. Conclusions: In the presence of carotenoid samples, the IM was mainly composed of Bacteroidota, Bacillota, Pseudomonadota and Actinomycetota phyla, promoting the growth of Lachnospiraceae bacteria while reducing the RA of Lactobacillus, Enterococcus, Streptococcus and Bifidobacterium. The Lycopene and Mix groups exhibited similar microbial compositions, whereas the β-carotene and Alga groups fostered a more diversified microbiota. The bacteria in the IM used glucose as a carbon source and were stimulated to produce significantly essential organic acids such as succinic, acetic, butyric and propionic acids.
- Depicting the suitability of FTIR to improve the differentiation of persistent and sporadic Listeria monocytogenesPublication . Meneses, Rui; Sousa, Clara; Teixeira, PaulaListeria monocytogenes is a ubiquitous Gram-positive pathogen that is particularly harmful to immunocompromised individuals. In food processing environments (FPEs), certain strains of L. monocytogenes are routinely isolated, while others are only encountered sporadically. One possible explanation for this recurrent isolation correlates with the presence of heterogeneous subpopulations, some of which can withstand adverse conditions encompassing high salinity, low temperature, and low pH, along with other FPEs-related stressors. We set out to evaluate the suitability of Fourier Transformed Infrared Atenuated Total Reflectance (FTIR-ATR) spectroscopy to discriminate between the fitest persistent specimens from the remaining sporadic subpopulations. 72 L. monocytogenes isolates, encompassing both persistent and sporadic L. monocytogenes, were grown in microtiter plates in the presence of different food-associated stressors (pH, T ºC, % NaCl), with growth curves obtained by measuring the optical density (OD600). After reaching the late exponential phase, the cell pellets were collected and analysed by FTIR-ATR spectroscopy. Additionally, infrared (IR) spectra of isolates grown in agar plates at 37ºC were collected. Partial Least-Squares Discriminant Analysis classification models based on collected IR spectra were developed to determine the viability of FTIR spectroscopy to discriminate persistence in different conditions. The gathered data showed no significant differences in growth rates and lag phases of persistent and sporadic L. monocytogenes in a planktonic state when grown at 37ºC or under the food-associated stressors tested. FTIR analysis has shown promising results in differentiating persistent and sporadic isolates belonging to the same serogroup, achieving correct assignment rates of over 70%.
- Clean label antimicrobial strategies for fungal spoilage of pastry fillingsPublication . Carvalho, Teresa Bento de; Silva, Beatriz Nunes; Azevedo, Miguel; Silva, Beatriz; Teixeira, PaulaIntroduction: Fungal spoilage is a key concern for the food industry, leading to hefty economic losses Consequently, the food waste that follows is also a grave matter not only due to its social or humanitarian aspect but also its environmental impact. Objectives: The aim of this study was to assess the antifungal activity of commercial clean label alternatives to potassium sorbate against moulds isolated from a pastry filling. Methodology: Isolation of fungi from a contaminated product used in antimicrobial activity tests of clean label preservatives. Results and discussion: Fungal growth was not completely inhibited at the concentrations recommended by the manufacturers. The antimicrobial agents are still effective and, therefore, a promising alternative to traditional chemical preservatives for the pastry industry. Conclusions: In this context, the clean label movement is trending to offer natural spoilage control strategies while having their organoleptic characteristics and, most importantly, safety in sight. Future research into the application of these antimicrobial compounds in pastry fillings is an important step to guarantee their efficacy and application in the industry.