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Percorrer CIMO por Domínios Científicos e Tecnológicos (FOS) "Ciências Médicas::Biotecnologia Médica"
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- Development of natural sporopollenin microcapsules: from bee pollen to versatile biomaterialsPublication . Aylanc, Volkan; Ertosun, Seymanur; Peixoto, Andreia F.; Santamaria-Echart, Arantzazu; Russo-Almeida, Paulo; Vale, Nuno; Freire, Cristina; Vilas-Boas, MiguelThe outer layer of the pollen grain, which plays a crucial role in the continuity of terrestrial plant life, has received significant attention due to its robustness, chemical inertness, and biocompatible structure made of sporopollenin. Herein, we present a straightforward method for producing high-purity (up to 97%) polymeric sporopollenin biocapsules (S-BioCaps) from bee pollen, exploring new plant sources for S-BioCaps, and diversifying the available morphologies to broaden the applications of pollen-based microcapsules. Following a purification process involving defatting, acidolysis, and several washing steps, we removed the inner components of the pollen grains and reduced the protein content to 2%. Confocal laser scanning and scanning electron microscopy images showed that the hollow and 3D S-BioCaps microstructure were preserved, while laser diffraction particle size analysis validated their monodisperse distribution across each pollen type within the size range of 15 to 24 μm. S-BioCaps tended to exhibit hydrophobic behavior when assessed through water dispersion and water marble analysis. Moreover, we sought to figure out the chemical changes occurring in specimens through Fourier-transform infrared analysis, and findings were consistent with simultaneous thermal analysis, where the thermal decomposition of sporopollenin biopolymer reached up to 457 °C. Overall, this work demonstrates a straightforward approach for utilizing pollen grains from Echium sp., Jasione sp., Papaver sp., Amaranthaceae, and Helianthemum sp., collected with the assistance of honeybees, to produce stable S-BioCaps with diverse morphologies, thereby broadening their potential applications as drug delivery microcarriers.
- Emergence, Spread of Antimicrobial-Resistant Bacteria and Phylogenetic Relationships in Coastal Ecosystems—Gastropod Phorcus lineatus as a BioindicatorPublication . Santos, Dércia; Pinto, Ana Rita; Barata, Rita; Fernandes, Conceição; Guedes, Hugo; Almeida, Gonçalo; Cabecinha, Edna; Monteiro, Sandra M.; Varandas, Simone; Saavedra, Maria JoséCoastal environments have been recognized as key reservoirs for antibiotic-resistant bacteria. The present study evaluated marine gastropods, Phorcus lineatus, as potential bioindicators to assess the spread of antibiotic-resistant bacteria. P. lineatus was sampled in four sites, with different anthropogenic pressures, along the northwest Portuguese coastal area. From these specimens, bacteria were isolated and tested for their antimicrobial susceptibility, followed by their phylogenetic and pathotypic determination. All the Escherichia coli isolates showed resistance to at least one antimicrobial agent. The highest levels of multidrug resistance (25%) were observed in E. coli isolates obtained from SITE 2, which is impacted by the city of Porto and industrial settlements, while nearly 17% of these isolates showed a multiple antibiotic resistance (MAR) index higher than 0.2. Among the isolates, phylogroups A and B2 were the most prevalent, followed by phylogroup B1. The isolates of phylogroup A showed a higher prevalence of antimicrobial resistance. This study offers valuable insights into the antibiotic resistance risks posed to marine ecosystems and underscores the need for microbiological monitoring and the development of effective management strategies. The findings suggest P. lineatus as a potential bioindicator of antibiotic-resistant bacteria in marine environments.
- Estratégia para mascarar o sabor amargo de fármacos em formulações orais pediátricasPublication . Pinto, Susana; Gomes, Joana; Ogbonna, John Dike N.; Cunha, Edite; Attama, Anthony A.; Ofokansi, Kenneth C.; Ferreira, Helena; Marx, Ítala; Peres, António M.; Lobo, José Manuel Sousa; Almeida, Isabel F.O sabor amargo de fármacos constitui uma barreira à adesão terapêutica em pediatria. Existem disponíveis várias estratégias para mascarar o amargor, mas a maioria é de difícil implementação na Farmácia Hospitalar (FH). Desenvolvimento de um veículo para administração oral para uso pediátrico, de composição simples e de fácil preparação, com o objetivo de mascarar o sabor amargo de um fármaco modelo com elevado índice de amargor (ranitidina). A estratégia adotada baseou ‑se na evidência bibliográfica da eficácia do cloreto de sódio na redução do amargor (2). As especificidades da população pediátrica e a facilidade de preparação e administração em FH foram também consideradas na definição da composição do veículo. A estabilidade química (características organoléticas, pH e doseamento por HPLC) e microbiológica foi avaliada durante 30 dias de armazenamento a 4°C e à temperatura ambiente. Removeu ‑se diariamente 1 mL da solução, de forma a simular a utilização. A capacidade do veículo mascarar o sabor amargo da ranitidina foi avaliada recorrendo a uma língua electrónica e comparada com um veículo de referência (xarope simples Formulário Galénico Português). A formulação desenvolvida apresenta uma composição simples que inclui uma associação de edulcorantes (sacarina sódica e aspartamo) e 0,1% de cloreto de sódio, e evidenciou uma maior eficácia em mascarar o amargor da ranitidina em comparação com o veículo de referência. A solução permaneceu estável durante 30 dias, armazenada a 4°C. Foram observadas diferenças nos perfis cromatográficos entre os protocolos de estabilidade (embalagem fechada ou simulação do uso), o que revela a contribuição da simulação do uso para a formação de produtos de degradação. A formulação pediátrica desenvolvida contém excipientes adequados a esta população, apresenta qualidade e estabilidade adequadas, estando otimizada para a preparação em FH. Este veículo revelou maior capacidade para mascarar o sabor amargo comparativamente ao xarope simples, não é cariogénico e é aplicável a diabéticos. Conclui ‑se também que os protocolos de estabilidade com simulação de uso devem ser preferidos na avaliação da estabilidade das formulações pediátricas. Este veículo tem aplicação na farmacoterapia pediátrica pela sua eficácia em mascarar o sabor amargo de fármacos e consequentemente promover a adesão à terapêutica.
- Estudio clínico-epidemiológico de la población de Bragança con sospecha de alergia al polen y a la espora fúngica Alternaria alternataPublication . Ferrage, Erica Vanessa Reis; Fraga, José; Feliciano, Manuel; Sánchez-Reyes, EstefaníaLa exposición al polen y a las esporas fúngicas constituye un factor ambiental crítico en la fisiopatología de las enfermedades respiratorias alérgicas, cuya prevalencia ha ido aumentando en entornos urbanos, caracterizados por condiciones ecológicas favorables. En este contexto, el presente estudio tuvo como objetivo caracterizar, desde el punto de vista clínico y epidemiológico, a la población de Bragança con sospecha de alergia al polen y a Alternaria alternata. Se trata de un estudio observacional, descriptivo, transversal y retrospectivo, basado en el análisis de 100 historias clínicas, con datos obtenidos mediante cuestionarios estructurados y pruebas cutáneas por punción (prick-test) con trece extractos alergénicos: doce polínicos y uno específico de Alternaria alternata. La muestra estuvo compuesta mayoritariamente por individuos de género femenino (53 %), con edad media de 23,9 ± 15,3 años, predominando residentes en zonas urbanas (86 %). El 42 % tenía animales de compañía, el 37 % presentaba exposición al tabaco y el 19 % vivía en viviendas con moqueta. Los síntomas más frecuentes fueron rinitis alérgica (99 %), rinoconjuntivitis (97 %), eccema (45 %) y sibilancias (44 %). Se observó polisensibilización en el 97 % de los participantes, con sensibilizaciones dirigidas a mezclas de gramíneas silvestres (96 %), gramíneas cultivadas (82 %), Olea europaea L. (80 %), mezclas de hierbas (78 %), Plantago lanceolata L. (75 %) y Alternaria alternata (Fr.) Keissl. (8 %). Estas evidencias permiten concluir un patrón de sensibilización compatible con alergias respiratorias en la población de Bragança.
- Exploring Phlomis crinita extracts: HPLC analysis, phenolic content, antioxidant and antimicrobial potentialsPublication . Chelgham, Abdelhakim; Saadi, Abdelkader; Merouane, Abdelaziz; Bensouıcı, Chawki; Cakmak, Yavuz Selim; Pires, Tânia C.S.P.Phlomis crinita Cav. (P. crinita), known as " Khayat el-djerah " in Algerian folk medicine, is used for wound healing and abdominal pain relief. This study assessed the phytochemical profile, phenolic content, antimicrobial activity against five Gram-negative and three Gram-positive clinical bacterial strains, as well as in vitro antioxidant activity of hydroethanolic extracts from leaves (HLE), flowers (HFE), and rhizomes (HRE) of P. crinita. Fifteen phenolic compounds such as four flavonoids, trans-cinnamic acid, six cinnamic acid derivatives, and four benzoic acid derivatives were identified for the first time in P. crinita by HPLC-DAD, with quantitative differences among the analyzed parts. HRE exhibited high levels of total phenolics (262.97 ± 16.2 μg GAE/mg DW) and flavonoids (71.87 ± 3.25 μg QE/mg DW), while HLE had the highest flavonols content (18.89 ± 5.12 μg QE/mg DW). All extracts demonstrated strong antioxidant properties. HLE exhibited the highest potency, with IC50 values of 15.46 ± 0.45 µg/mL (DPPH) and 11.71 ± 0.50 µg/mL (ABTS). HLE exhibited good reducing power (FRAP A0.5 = 40.07 ± 2.82 µg/mL), while HRE showed the best reducing power (Phenanthroline A0.5 = 7.88 ± 1.63 µg/mL). All extracts revealed broad-spectrum antibacterial effects, and HRE exhibited the most potent activity against Enterococcus faecalis, with a minimum inhibitory concentration (MIC) value of 1.25 mg/mL. These results showed that P. crinita could be useful as source of bioactive compounds for pharmaceutical and food industry.
- In Silico Identification of Six Mushroom-Derived Sterol and Triterpenoid Compounds as Potential P-Glycoprotein Modulators in Multidrug ResistancePublication . Fonseca, Jéssica; Shiraishi, Carlos S.H.; Abreu, Rui M.V.; Ricardo, Sara; Vaz, Josiana A.The overexpression of P-glycoprotein (P-gp) is often directly related to multidrug resistance (MDR), one of the greatest challenges in cancer treatment. This transmembrane efflux pump decreases the intracellular concentrations of chemotherapy drugs, reducing their effectiveness and resulting in treatment failure. This work used in silico methods to assess the potential of bioactive chemicals produced from mushrooms as P-gp modulators. A database comprising 211 bioactive compounds from mushrooms was investigated using molecular docking and virtual screening techniques against the P-gp structure. The compounds ergosta-4,6,8(14),22-tetraen-3-one, lucidumol A, (22E,24S)-ergosta-4,22-dien-3-one, antcin K, 3,11-dioxolanosta-8,24(Z)-diene-26-oic acid, and (22E)-19-norergosta-5,7,9,22-tetraen-3 beta-ol were identified as the six best candidates from our database of mushroom compounds based on their binding affinities, toxicity predictions, and pharmacological properties assessed through ADME analyses (absorption, distributions, metabolism, and excretion). These six compounds exhibited strong binding affinities, with binding energies ranging from -12.31 kcal/mol to -10.93 kcal/mol, all showing higher affinities than the control, tariquidar, which had a binding energy of -10.78 kcal/mol. Toxicity predictions indicated favorable safety profiles for all six, while ADME analyses found that all six compounds had high oral bioavailability and a low probability of acting as P-gp substrates. These results position bioactive mushroom compounds, particularly these six, as promising P-gp modulators, suggesting positive outcomes in cancer treatment.
- Inactivation of Staphylococcus aureus by antimicrobial photodynamic therapy using 1,9-Dimethyl-Methylene Blue: in vitro and in vivo studiesPublication . Brito Júnior, Anildo Alves de; Crugeira, Pedro; Barbosa, Andressa Vollono; Costa, Wellington Luis Reis; Cangussu, Maria Cristina Teixeira; Oliveira, Susana Carla Pires Sampaio de; Pinheiro, Antônio Luiz Barbosa; Melo, Amanda Inês Vieira de; Pinheiro, Antônio Luiz Barbosa; Azevedo, Juliana MonteiroThe efficiency of antibiotics in terms of their bacterial inhibition is well known. However, studies show that its overuse, underuse, and misuse induce antimicrobial resistance, promoting the need to work with alternative methods. In this sense, antimicrobial photodynamic therapy (aPDT) is a promising selective method demonstrating excellent response. This study aimed to evaluate the antimicrobial action promoted in Staphylococcus aureus using 1,9 dimethyl methylene blue dye (DMMB) combined with red LED (λ 630 ± 20 nm, CW, 125 mW, 12 J/ cm², 192 s) in planktonic culture and rats skin wounds contaminated with staphylococcal bacteria. The experimental in vitro and in vivo groups were Control, LED, DMMB, and LED + DMMB; after aPDT, the triplicate samples for each dilution were incubated for 24 h, and the number of bacteria was determined by counting the colony-forming units, and the logarithm (CFU/mL log). Based on in vitro data obtained, the LED + DMMB group, when compared to the Control, showed a reduction in microbial load of 99.943% (p < 0.0001), with decimal reduction (RD = 3). Whereas in vivo results, the same comparing groups demonstrated a reduc- tion in microbial load, reaching 99.994% (RD = 4). In this research, the aPDT was a unique treatment, and it is possible to repeat it to obtain higher microbial reduction, providing an alternative therapeutic that can be clinically validated to combat infections caused by S. aureus.
- Liposomal co-formulation of Azure A and rose bengal decyl ester as a multi-cellular target approach for photodynamic therapy of colorectal cancerPublication . Silva, Ana Claudia Pedrozo da; Freitas, Camila Fabiano de; Calori, Italo Rodrigo; Tedesco, Antonio Claudio; Silvestrin, Amanda Gratão; Silva, Leandro Herculano da; Speziali, Maria Ida Bonini Ravanelli; Hioka, Noboru; Tessaro, André LuizMultidrug systems offer a promising strategy to improve the efficacy of anticancer treatments, reduce therapeutic doses, and attenuate side effects. In this study, the photosensitizers Azure A (AA) and rose bengal decyl ester (RBDEC) were co-encapsulated in hybrid DPPC/F127 liposomes to target multiple cellular sites. The combined system yielded small unilamellar vesicles (SUVs) with a polydispersity index suitable for biological applications and a zeta potential of +10.57 mV. The encapsulation efficiency of AA and RBDEC is 60.3 and 98.5 %, respectively. In the colorectal adenocarcinoma Caco-2 cells line, photosensitizers showed distinct cellular localization, with RBDEC most targeting the nuclear region and AA the cytoplasm confirmed by confocal microscopy. According to the Chou-Talalay method for drug combinations, the equimolar and lower concentrations (2.5 x 10_6 mol L_ 1 each) exhibited an additive effect, suggesting that even lower concentrations could achieve synergism. The findings indicate that this system exhibits considerable promise, as the combination of drugs facilitates action at multiple sites, thereby increasing the likelihood of cell death. In addition, the system demonstrated greater efficiency at lower concentrations, reducing adverse effects and directing future studies.
- Propolis-Loaded Niosomes for Dermopharmaceutic and Cosmetic Applications: Development, Stability, Safety, and In Vitro Bioactivity StudiesPublication . Pinto, Maria Beatriz; Pires, Patrícia C.; Correia, Mafalda; Moço, Gabriela; Sousa-Oliveira, Inês; Sousa, Maria João; Calhelha, Ricardo C.; Vilas-Boas, Miguel; Falcão, Soraia; Mazzola, Priscila Gava; Veiga, Francisco; Paiva-Santos, Ana CláudiaPropolis, produced by Apis melliferabees, is composed of several biologically relevant phenolic compounds with known analgesic, anti-inflammatory, antitumor, antioxidant, immunomodulatory, wound healing, and antibacterial effects, having gained significant interest for therapeutic and cosmetic purposes. Niosomes, self-assembled vesicular nanosystems, are highly researched for topical delivery due to providing controlled and sustained release, protecting encapsulated compounds from degradation, improving stability, and having good biocompatibility and biodegradability. This work aimed to develop novel propolis-loaded niosomes with small and homogeneous particle size, high encapsulation efficiency, controlled release, adequate stability, relevant bioactivity, and high safety for topical application, for therapeutic and/or cosmetic purposes. Aided by quality by design (QbD) analysis, niosomes containing Tween 20, Kolliphor RH 40, cetyl alcohol, and/or cholesterol were produced by thin-film hydration followed by extrusion, with small particle size (between 100 and 200 nm), homogeneous distribution (PDI below 0.2), relevant zeta-potential (around -38 mV), good stability both under refrigeration and at room temperature, high encapsulation efficiency (ranging from 78.8 to 87.4%), and a controlled release profile, relevant to ensure prolonged bioactivity at the application site. Adequate concentration-dependent in vitro safety in keratinocytes and fibroblasts (up to 12.5 or 25 mu g/mL) was demonstrated as well, with some niosomal formulations also showing a low irritative potential in a HET-CAM test, and relevant in vitro anti-inflammatory potential (IC50 from 14.90 to 17.89 ng/mL). These novel nanoplatforms, containing a nature-derived hydrophobic compound with various relevant bioactivities, could serve as versatile and advantageous formulations in both pharmaceutical and cosmetic contexts of application.