33 documents found, page 1 of 4
Fluorescent quantification of melanin
Fernandes, Bruno Pacheco; Matamá, Maria Teresa; Guimarães, Diana Isabel Pereira; Gomes, Andreia C; Cavaco-Paulo, ArturMelanin quantification is reportedly performed by absorption spectroscopy, commonly at 405 nm. Here, we propose the implementation of fluorescence spectroscopy for melanin assessment. In a typical in vitro assay to assess melanin production in response to an external stimulus, absorption spectroscopy clearly overvalues melanin content. This method is also incapable of distinguishing non-melanotic/amelanotic con...
Cutinase promotes dry esterification of cotton cellulose
Zhao, X.; Matamá, Maria Teresa; Ribeiro, Artur J.; Silva, Carla; Wu, Jing; Fu, Jiajia; Cavaco-Paulo, ArturCutinase from Thermobifida fusca was used to esterify the hydroxyl groups of cellulose with the fatty acids from triolein. Cutinase and triolein were pre-adsorbed on cotton and the reaction proceeded in a dry state during 48 hours at 35ºC. The cutinase-catalyzed esterification of the surface of cotton fabric resulted in the linkage of the oleate groups to the glycoside units of cotton cellulose. The superficial...
A biologically active delivery material with dried-rehydrated vesicles containi...
Ferreira, Helena; Silva, Raquel; Matamá, Maria Teresa; Silva, Carla; Gomes, Andreia C; Cavaco-Paulo, ArturAbstractChronic wounds usually remain in the inflammatory phase of the healing process during several months or even years. Hence, a continuous research has been resulting in the development of wound dressings with improved performance. Herein, we report a delivery system for cutaneous wound healing, consisting of a textile material (non-woven gauzes) covered with lipidic vesicles containing diclofenac, a non-s...
Enzymatic synthesis of poly(catechin)-antibiotic conjugates: an antimicrobial a...
Gonçalves, Idalina; Abreu, Ana S.; Matamá, Maria Teresa; Ribeiro, Artur J.; Gomes, Andreia C; Silva, Carla Manuela Pereira Marinho daBiofilm formation in urinary indwelling catheters is one of the most critical issues that patients face. Catheters were coated with poly(catechin)-antibiotic conjugates with enhanced antimicrobial properties. Catechin was conjugated with two antibiotics, namely trimethoprim (TMP) and sulfamethoxazole (SMZ) via activation with N,N′-disuccinimidyl carbonate (DSC) and subsequent coupling to molecules containing α-...
Hair coloration by gene regulation: fact or fiction?
Matamá, Maria Teresa; Gomes, Andreia C; Cavaco-Paulo, ArturThe unravelling of hair pigmentation genetics and robust delivery systems to the hair follicle (HF) will allow the development of a new class of colouring products. The challenge will be changing hair colour from inside out by safely regulating the activity of target genes through the specific delivery of synthetic/natural compounds, proteins, genes, or small RNAs.
Improved Poly (D,L-lactide) nanoparticles-based formulation for hair follicle t...
Fernandes, Bruno Pacheco; Silva, R.; Ribeiro, Artur J.; Matamá, Maria Teresa; Gomes, Andreia C; Paulo, Artur CavacoObjective Hair follicles are widely recognized as the preferential target and site of accumulation for nanoparticles after topical application. This feature is of particular importance for hair cosmetics, having the potential to refine the treatment of several hair follicle-related disorders. The aim of this work was to improve the preparation of Poly (D,L-lactide) (PLA) nanoparticles for in vivo follicular tar...
Assessment of a protease inhibitor peptide for anti-ageing
Sá, M.; Azóia, Nuno G.; Carvalho, Ana C.; Silva, C.; Matamá, Maria Teresa; Gomes, Andreia C; Cavaco-Paulo, ArturAgeing and skin exposure to UV radiation induces production and activation of matrix metalloproteinases (MMPs) and human neutrophil elastase (HNE). These enzymes are known to break down the extracellular matrix (ECM) which leads to wrinkle formation. Here, we demonstrated the potential of a solid-in-oil nanodispersion containing a competitive inhibitor peptide of HNE mixed with hyaluronic acid (HA), displaying ...
Odorant binding proteins: a biotechnological tool for odour control
Silva, Carla Manuela Pereira Marinho da; Matamá, Maria Teresa; Azóia, Nuno G.; Mansilha, Catarina; Casal, Margarida; Paulo, Artur CavacoThe application of an odorant binding protein for odour control and fragrance delayed release from a textile surface was first explored in this work. Pig OBP-1 gene was cloned and expressed in Escherichia coli , and the purified protein was biochemically characterized. The IC50 values(concentrations of competitor that caused a decay of fluorescence to half-maximal intensity) were determined for four distinct fr...
Laccase coating of catheters with poly(catechin) for biofilm reduction
Gonçalves, Idalina; Matamá, Maria Teresa; Paulo, Artur Cavaco; Silva, Carla Manuela Pereira Marinho daUrinary polyurethane (PU) and silicone (SI) catheters were coated with poly(catechin) to reduce bacterial adhesion. Laccase was used as a biocatalyst to oxidize the catechin monomer and produce the polymer. Optimization of the catheter surface functionalization followed two different approaches: with or without previous alkali treatment. The results indicated higher levels of polymer attachment for the alkali-t...
Design of novel BSA/hyaluronic acid nanodispersions for transdermal pharma purp...
Martins, Madalena A.; Azóia, Nuno G.; Shimanovich, Ulyana; Matamá, Maria Teresa; Gomes, Andreia C; Silva, Carla Manuela Pereira Marinho daA novel transdermal hyaluronic acid (HA) conjugated with bovine serum albumin (BSA) was developed in the form of solid-in-oil (S/O) nanodispersion (129.7 nm mean diameter). Ex vivo skin penetration analysis by fluorescence and confocal observation of histological skin sections revealed the ability of BSA/HA nanodispersions to cross the stratum corneum and penetrate into the dermis. Furthermore, no significant t...