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1.
J Agric Food Chem ; 72(15): 8372-8379, 2024 Apr 17.
Article in English | MEDLINE | ID: mdl-38579274

ABSTRACT

Self-assembling peptides are rapidly gaining attention as novel biomaterials for food and biomedical applications. Peptides self-assemble when triggered by physical or chemical factors due to their versatile physicochemical characteristics. Peptide self-assembly, when combined with the health-promoting bioactivity of peptides, can also result in a plethora of biofunctionalities of the biomaterials. This perspective highlights current developments in the use of food-derived self-assembling peptides as biomaterials, bioactive nutraceuticals, and potential dual functioning bioactive biomaterials. Also discussed are the challenges and opportunities in the use of self-assembling bioactive peptides in designing biocompatible, biostable, and bioavailable multipurpose biomaterials.


Subject(s)
Biocompatible Materials , Peptides , Hydrogels , Dietary Supplements
2.
Adv Colloid Interface Sci ; 325: 103100, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38330882

ABSTRACT

Synthetic polymers, particularly polyurethanes (PUs), have revolutionized bioengineering and biomedical devices due to their customizable mechanical properties and long-term stability. However, the inherent hydrophobic nature of PU surfaces arises common issues such as high friction, strong protein adsorption, and thrombosis, especially in the physiological environment of blood contact. To overcome these issues, researchers have explored various modification techniques to improve the surface biofunctionality of PUs. In this review, we have systematically summarized several typical surface modification methods including surface plasma modification, surface oxidation-induced grafting polymerization, isocyanate-based chemistry coupling, UV-induced surface grafting polymerization, adhesives-assisted attachment strategy, small molecules-bridge grafting, solvent evaporation technique, and hydrogen bonding interaction. Correspondingly, the advantages, limitations, and future prospects of these surface modification methods were discussed. This review provides an important guidance or tool for developing surface functionalized PUs in the fields of bioengineering and medical devices.

3.
Adv Healthc Mater ; 13(16): e2303167, 2024 06.
Article in English | MEDLINE | ID: mdl-38400658

ABSTRACT

Most tissues of the human body present hierarchical fibrillar extracellular matrices (ECMs) that have a strong influence over their physicochemical properties and biological behavior. Of great interest is the introduction of this fibrillar structure to hydrogels, particularly due to the water-rich composition, cytocompatibility, and tunable properties of this class of biomaterials. Here, the main bottom-up fabrication strategies for the design and production of hierarchical biomimetic fibrillar hydrogels and their most representative applications in the fields of tissue engineering and regenerative medicine are reviewed. For example, the controlled assembly/arrangement of peptides, polymeric micelles, cellulose nanoparticles (NPs), and magnetically responsive nanostructures, among others, into fibrillar hydrogels is discussed, as well as their potential use as fibrillar-like hydrogels (e.g., those from cellulose NPs) with key biofunctionalities such as electrical conductivity or remote stimulation. Finally, the major remaining barriers to the clinical translation of fibrillar hydrogels and potential future directions of research in this field are discussed.


Subject(s)
Biomimetic Materials , Hydrogels , Tissue Engineering , Tissue Scaffolds , Humans , Tissue Scaffolds/chemistry , Hydrogels/chemistry , Tissue Engineering/methods , Biomimetic Materials/chemistry , Animals , Extracellular Matrix/chemistry , Regenerative Medicine/methods
4.
Int J Biol Macromol ; 262(Pt 2): 130194, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38360222

ABSTRACT

Gelatin methacrylate (GelMA) bioink has been widely used in bioprinting because it is a printable and biocompatible biomaterial. However, it is difficult to print GelMA bioink without any temperature control because it has a thermally-sensitive rheological property. Therefore, in this study, we developed a temperature-controlled printing system in real time without affecting the viability of the cells encapsulated in the bioink. In addition, a skin-derived decellularized extracellular matrix (SdECM) was printed with GelMA to better mimic the native tissue environment compared with solely using GelMA bioink with the enhancement of structural stability. The temperature setting accuracy was calculated to be 98.58 ± 1.8 % for the module and 99.48 ± 1.33 % for the plate from 5 °C to 37 °C. The group of the temperature of the module at 10 °C and the plate at 20 °C have 93.84 % cell viability with the printable range in the printability window. In particular, the cell viability and proliferation were increased in the encapsulated fibroblasts in the GelMA/SdECM bioink, relative to the GelMA bioink, with a morphology that significantly spread for seven days. The gene expression and growth factors related to skin tissue regeneration were relatively upregulated with SdECM components. In the bioprinting process, the rheological properties of the GelMA/SdECM bioink were successfully adjusted in real time to increase printability, and the native skin tissue mimicked components providing tissue-specific biofunctions to the encapsulated cells. The developed bioprinting strategies and bioinks could support future studies related to the skin tissue reconstruction, regeneration, and other medical applications using the bioprinting process.


Subject(s)
Gelatin , Tissue Scaffolds , Tissue Scaffolds/chemistry , Gelatin/chemistry , Methacrylates/chemistry , Printing, Three-Dimensional , Biocompatible Materials , Tissue Engineering
5.
Front Cell Dev Biol ; 11: 1214118, 2023.
Article in English | MEDLINE | ID: mdl-37920826

ABSTRACT

Antibody therapeutics are limited in treating brain diseases due to poor blood-brain barrier (BBB) penetration. We have discovered that poly 2-methacryloyloxyethyl phosphorylcholine (PMPC), a biocompatible polymer, effectively facilitates BBB penetration via receptor-mediated transcytosis and have developed a PMPC-shell-based platform for brain delivery of therapeutic antibodies, termed nanocapsule. Yet, the platform results in functional loss of antibodies due to epitope masking by the PMPC polymer network, which necessitates the incorporation of a targeting moiety and degradable crosslinker to enable on-site antibody release. In this study, we developed a novel platform based on site-oriented conjugation of PMPC to the antibody, allowing it to maintain key functionalities of the original antibody. With an optimized PMPC chain length, the PMPC-antibody conjugate exhibited enhanced brain delivery while retaining epitope recognition, cellular internalization, and antibody-dependent cellular phagocytic activity. This simple formula incorporates only the antibody and PMPC without requiring additional components, thereby addressing the issues of the nanocapsule platform and paving the way for PMPC-based brain delivery strategies for antibodies.

6.
Bioact Mater ; 19: 717-757, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35633903

ABSTRACT

Mg and its alloys evince strong candidature for biodegradable bone implants, cardiovascular stents, and wound closing devices. However, their rapid degradation rate causes premature implant failure, constraining clinical applications. Bio-functional surface coatings have emerged as the most competent strategy to fulfill the diverse clinical requirements, besides yielding effective corrosion resistance. This article reviews the progress of biodegradable and advanced surface coatings on Mg alloys investigated in recent years, aiming to build up a comprehensive knowledge framework of coating techniques, processing parameters, performance measures in terms of corrosion resistance, adhesion strength, and biocompatibility. Recently developed conversion and deposition type surface coatings are thoroughly discussed by reporting their essential therapeutic responses like osteogenesis, angiogenesis, cytocompatibility, hemocompatibility, anti-bacterial, and controlled drug release towards in-vitro and in-vivo study models. The challenges associated with metallic, ceramic and polymeric coatings along with merits and demerits of various coatings have been illustrated. The use of multilayered hybrid coating comprising a unique combination of organic and inorganic components has been emphasized with future perspectives to obtain diverse bio-functionalities in a facile single coating system for orthopedic implant applications.

7.
Environ Sci Technol ; 56(12): 8132-8141, 2022 06 21.
Article in English | MEDLINE | ID: mdl-35561278

ABSTRACT

Fungal-mineral interactions can effectively alleviate cellular stress from organic pollutants, the production of which are expected to rapidly increase owing to the Earth moving into an unprecedented geological epoch, the Anthropocene. The underlying mechanisms that may enable fungi to combat organic pollution during fungal-mineral interactions remain unclear. Inspired by the natural fungal sporulation process, we demonstrate for the first time that fungal biomineralization triggers the formation of an ultrathin (hundreds of nanometers thick) exoskeleton, enriched in nanosized iron (oxyhydr)oxides and biomolecules, on the hyphae. Mapped biochemical composition of this coating at a subcellular scale via high spatial resolution (down to 50 nm) synchrotron radiation-based techniques confirmed aromatic C, C-N bonds, amide carbonyl, and iron (oxyhydr)oxides as the major components of the coatings. This nanobiohybrid system appeared to impart a strong (×2) biofunctionality for fungal degradation of bisphenol A through altering molecular-level trade-offs between lattice oxygen and oxygen vacancy. Together, fungal coatings could act as "artificial spores", which enable fungi to combat physical and chemical stresses in natural environments, providing crucial insights into fungal biomineralization and coevolution of the Earth's lithosphere and biosphere.


Subject(s)
Environmental Pollutants , Exoskeleton Device , Iron , Minerals/chemistry , Oxides/chemistry , Oxygen
8.
Nanomaterials (Basel) ; 12(3)2022 Feb 07.
Article in English | MEDLINE | ID: mdl-35159914

ABSTRACT

Metallic implants (mesh) for guided bone regeneration can result in foreign body reactions with surrounding tissues, infection, and inflammatory reactions caused by micro-organisms in the oral cavity after implantation. This study aimed to reduce the possibility of surgical failure caused by microbial infection by loading antibacterial manuka oil in a biocompatible nanostructure surface on Ti and to induce stable bone regeneration in the bone defect. The manuka oil from New Zealand consisted of a rich ß-triketone chemotype, leptospermone, which showed strong inhibitory effects against several bacteria, even at very low oil concentrations. The TiO2 nanotubular layer formed by anodization effectively enhanced the surface hydrophilicity, bioactivity, and fast initial bone regeneration. A concentration of manuka oil in the range of 0.02% to less than 1% can have a synergistic effect on antibacterial activity and excellent biocompatibility. A manuka oil coating (especially with a concentration of 0.5%) on the TiO2 nanotube layer can be expected not only to prevent stenosis of the connective tissue around the mesh and inflammation by microbial infection but also to be effective in stable and rapid bone regeneration.

9.
Clin Hemorheol Microcirc ; 80(3): 327-341, 2022.
Article in English | MEDLINE | ID: mdl-34542065

ABSTRACT

Multiblock copolymers type PDC are polyetheresterurethanes composed of poly(ɛ-caprolactone) and poly(p-dioxanone) segments. They were designed as degradadable shape-memory polymers for medical devices, which can be implanted minimally-invasively. While providing structural support in the initial phase after implantation, they are capable to modulate soft tissue regeneration while degradation. In this perspective, we elucidate cell-material interactions, compatibility both in-vitro and in-vivo and biofunctionality of PDC, which represents a promising candidate biomaterial family especially for cardiovascular applications.


Subject(s)
Biocompatible Materials , Polyesters , Biocompatible Materials/chemistry , Biocompatible Materials/therapeutic use , Polyesters/chemistry
10.
Exp Ther Med ; 22(5): 1315, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34630669

ABSTRACT

Biocompatibility is one of the mandatory requirements for the clinical use of biomaterials in orthopedics. It refers to the ability of a biomaterial to perform its function without eliciting toxic or injurious effects on biological systems but producing an appropriate host response in a specific case. Today, the biocompatibility concept includes not only bio-inertia, but also biofunctionality and biostability. High biocompatibility and functional properties are highly desirable for new biomaterials. The chemical, mechanical, structural properties of biomaterials, their interaction with biological environment or even the methodology of assessment can influence the biocompatibility. The biological evaluation of biomaterials includes a broad spectrum of in vitro and in vivo tests related to the cytocompatibility, genotoxicity, sensitization, irritation, acute and chronic toxicity, hemocompatibility, reproductive and developmental toxicitity, carcinogenicity, implantation and degradation as specified in different international standards. A brief review of the main assays used in the biocompatibility testing of orthopedic biomaterials is presented. In addition, their main biocompatibility issues are overviewed.

11.
Materials (Basel) ; 14(14)2021 Jul 08.
Article in English | MEDLINE | ID: mdl-34300727

ABSTRACT

Cation-substituted hydroxyapatite (HA), standalone or as a composite (blended with polymers or metals), is currently regarded as a noteworthy candidate material for bone repair/regeneration either in the form of powders, porous scaffolds or coatings for endo-osseous dental and orthopaedic implants. As a response to the numerous contradictions reported in literature, this work presents, in one study, the physico-chemical properties and the cytocompatibility response of single cation-doped (Ce, Mg, Sr or Zn) HA nanopowders in a wide concentration range (0.5-5 at.%). The modification of composition, morphology, and structure was multiparametrically monitored via energy dispersive X-ray, X-ray photoelectron, Fourier-transform infrared and micro-Raman spectroscopy methods, as well as by transmission electron microscopy and X-ray diffraction. From a compositional point of view, Ce and Sr were well-incorporated in HA, while slight and pronounced deviations were observed for Mg and Zn, respectively. The change of the lattice parameters, crystallite size, and substituting cation occupation factors either in the Ca(I) or Ca(II) sites were further determined. Sr produced the most important HA structural changes. The in vitro biological performance was evaluated by the (i) determination of leached therapeutic cations (by inductively coupled plasma mass spectrometry) and (ii) assessment of cell behaviour by both conventional assays (e.g., proliferation-3-(4,5-dimethyl thiazol-2-yl) 5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay; cytotoxicity-lactate dehydrogenase release assay) and, for the first time, real-time cell analysis (RTCA). Three cell lines were employed: fibroblast, osteoblast, and endothelial. When monophasic, the substituted HA supported the cells' viability and proliferation without signs of toxicity. The RTCA results indicate the excellent adherence of cells. The study strived to offer a perspective on the behaviour of Ce-, Mg-, Sr-, or Zn-substituted HAs and to deliver a well-encompassing viewpoint on their effects. This can be highly important for the future development of such bioceramics, paving the road toward the identification of candidates with highly promising therapeutic effects.

12.
Appl Microbiol Biotechnol ; 105(11): 4635-4648, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34059939

ABSTRACT

Currently, the lack of reliable strategies for the diagnosis and treatment of cancer makes the identification and characterization of new therapeutic targets a pressing matter. Several studies have proposed the Six Transmembrane Epithelial Antigen of the Prostate 1 (STEAP1) as a promising therapeutic target for prostate cancer. Although structural and functional studies may provide deeper insights on the role of STEAP1 in cancer, such techniques require high amounts of purified protein through biotechnological processes. Based on the results presented, this work proposes the application, for the first time, of a fed-batch profile to improve STEAP1 biosynthesis in mini-bioreactor Komagataella pastoris X-33 Mut+ methanol-induced cultures, by evaluating three glycerol feeding profiles-constant, exponential, and gradient-during the pre-induction phase. Interestingly, different glycerol feeding profiles produced differently processed STEAP1. This platform was optimized using a combination of chemical chaperones for ensuring the structural stabilization and appropriate processing of the target protein. The supplementation of culture medium with 6 % (v/v) DMSO and 1 M proline onto a gradient glycerol/constant methanol feeding promoted increased biosynthesis levels of STEAP1 and minimized aggregation events. Deglycosylation assays with peptide N-glycosidase F showed that glycerol constant feed is associated with an N-glycosylated pattern of STEAP1. The biological activity of recombinant STEAP1 was also validated, once the protein enhanced the proliferation of LNCaP and PC3 cancer cells, in comparison with non-tumoral cell cultures. This methodology could be a crucial starting point for large-scale production of active and stable conformation of recombinant human STEAP1. Thus, it could open up new strategies to unveil the structural rearrangement of STEAP1 and to better understand the biological role of the protein in cancer onset and progression.


Subject(s)
Antigens, Neoplasm/biosynthesis , Glycerol , Methanol , Oxidoreductases/biosynthesis , Recombinant Proteins/biosynthesis , Humans , Pichia , Promoter Regions, Genetic , Saccharomycetales
13.
Rev. ADM ; 76(6): 328-331, nov.-dic. 2019. ilus
Article in Spanish | LILACS | ID: biblio-1087384

ABSTRACT

La odontología deportiva es la rama de la medicina deportiva que se ocupa de la prevención y el tratamiento de las lesiones bucodentales y las enfermedades orales asociadas al deporte y el ejercicio. Por lo que se hace necesario la intervención de profesionales de la salud bucodental para hacer evaluaciones del deportista y el deporte que practica para ver los riesgos que puede tener de desarrollar y sufrir lesiones bucodentales como traumas dentoalveolares y lesiones no cariosas. Y de este modo realizar las recomendaciones a cada paciente que practica deporte, de los elementos que deben usar como equipamiento bucodental para evitar o reducir el daño dentoalveolar (AU)


Sports dentistry is the branch of sports medicine that deals with the prevention and treatment of oral injuries and oral diseases associated with sports and exercise. Therefore it is necessary the intervention of oral health professionals to make evaluations of the athlete and the sport he practices to see the risks that may have to develop and suffer oral injuries such as dentoalveolar trauma and non-carious lesions. And in this way make the recommendations to each patient who practices sports, of the elements that should be used as oral equipment to avoid or reduce dentoalveolar damage (AU)


Subject(s)
Humans , Athletic Injuries , Sports , Tooth Injuries/prevention & control , Mouth Protectors , Phenotype , Stomatognathic System/physiology , Tooth Socket/injuries , Dental Enamel/injuries , Dentin/injuries
14.
Foods ; 8(8)2019 Aug 12.
Article in English | MEDLINE | ID: mdl-31409056

ABSTRACT

An objective of the present study was the enrichment of skim sheep yoghurt milk base with hydrolysates (WPHs) of whey protein concentrate (WP80) derived from Feta cheesemaking. Moreover, the use of high hydrostatic pressure (HP) treatment at 600 MPa/55 C/10 min as an alternative for heat treatment of milk bases, was studied. In brief, lyophilized trypsin and protamex hydrolysates of WP80 produced under laboratory conditions were added in skim sheep milk. The composition and heat treatment conditions were set after the assessment of the heat stability of various mixtures; trisodium citrate was used as a chelating agent, when needed. According to the results, the conditions of heat treatment were more important for the physical properties of the gel than the type of enrichment. High pressure treatment resulted in inferior gel properties, irrespective of the type of enrichment. Supplementation of skim sheep milk with whey protein hydrolysates at >0.5% had a detrimental effect on gel properties. Finally, skim sheep milk base inoculated with fresh traditional yoghurt, resulted in yoghurt-type gels with high counts of Lb. delbrueckii subsp. bulgaricus and Str. thermophilus -close to the ideal 1:1- and with a high ACE inhibitory activity >65% that were not essentially affected by the experimental factors.

15.
Nanomaterials (Basel) ; 9(6)2019 May 29.
Article in English | MEDLINE | ID: mdl-31146416

ABSTRACT

Diamond-like carbon (DLC) coatings are well known as protective coatings for biomedical applications. Furthermore, the incorporation of different elements, such as silicon (Si), in the carbon matrix changes the bio-functionality of the DLC coatings. This has also been proven by the results obtained in this work. The Si-DLC coatings were deposited on the Ti6Al7Nb alloy, which is commonly used in clinical practice, using the magnetron sputtering method. According to the X-ray photoelectron spectroscopy (XPS) analysis, the content of silicon in the examined coatings varied from ~2 at.% up to ~22 at.%. Since the surface characteristics are key factors influencing the cell response, the results of the cells' proliferation and viability assays (live/dead and XTT (colorimetric assays using tetrazolium salt)) were correlated with the surface properties. The surface free energy (SFE) measurements, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS) analysis demonstrated that the polarity and wettability of the surfaces examined increase with increasing Si concentration, and therefore the adhesion and proliferation of cells was enhanced. The results obtained revealed that the biocompatibility of Si-doped DLC coatings, regardless of the Si content, remains at a very high level (the observed viability of endothelial cells is above 70%).

16.
Int J Biol Macromol ; 134: 575-587, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31067487

ABSTRACT

In this study, we assessed the bio-functional attributes of an exopolysaccharide (EPS) produced by the actinobacterial probiont Streptomyces griseorubens GD5. The EPS production was doubled to 9.50 g/L by varying the concentration of media components using Response surface methodology. The physio-chemical properties of GD5EPS were examined by various analytical techniques. Several functional groups were detected in FT-IR spectra, including ß-glycosidic linkages, hydroxyl, carboxyl, and amide groups. Glucose, galactose, and mannose were detected from NMR spectra whilst the occurrence of arabinose, glucose, galactose, mannose, and xylose, were detected from HPLC chromatogram, signifying that GD5EPS is heteropolysaccharide in nature. The thermogram profile and SEM-EDX spectra of the extracted EPS indicated that it was highly thermo-stable, compact and porous, with flake-like structural units with the elemental composition of C, O, P, Mg, K, Ca, and Na. The GD5EPS also revealed potential antioxidant, emulsifying and antibiofilm efficacies, which corroborated that EPS derived from S. griseorubens GD5 might be a promising food supplement.


Subject(s)
Polysaccharides, Bacterial/pharmacology , Probiotics/chemistry , Streptomyces/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/chemistry , Antioxidants/pharmacology , Biofilms/drug effects , Chelating Agents/chemistry , Chelating Agents/pharmacology , Chemical Phenomena , Monosaccharides/chemistry , Monosaccharides/pharmacology , Polysaccharides, Bacterial/chemistry , Polysaccharides, Bacterial/ultrastructure , Spectrum Analysis , Streptomyces/growth & development
17.
Anim Sci J ; 90(7): 903-912, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31012203

ABSTRACT

The value-added products in livestock industry is one of the key issues in order to maximize the revenue and to create a new business model. Numerous studies have suggested application of herbal plants as feed additives to increase health, productivity, and/or high-quality product in livestock. In this study, the first experiment was designed to develop in vitro evaluation system by using primary chicken myoblast (pCM) cells isolated from pectoralis major of 10-day-old male embryos. Subsequently, to evaluate effects of Korean Danggui Angelica gigas Nakai (AGN), we optimized the concentration of AGN root extract for treatment of primary pCM cells. After the treatment of AGN root extract, we compared proliferation and differentiation capacity, and also examined the gene expression. In the second experiment, the next generation sequencing analysis was performed to compare the different patterns of the global gene expression in pCM cells treated with AGN extract. Three up-regulated (pancreas beta cells, fatty acid metabolism and glycolysis) and one down-regulated (adipogenesis) gene sets were characterized suggesting that the AGN extract affected the metabolic pathways for the utilization of fat and glucose in chicken muscle cells. Furthermore, we validated the expression patterns of the up-regulated genes (GCLC, PTPN6, ISL1, SLC25A13, TGFBI, and YWHAH) in the AGN-treated pCM cells by quantitative RT-PCR. These results demonstrated that the treatment of AGN extract decreased proliferation and differentiation of pCM cells, and affected the metabolic pathways of glucose and fatty acids. Moreover, AGN extract derived from byproducts such as stem and leaf also showed the reduced proliferation patterns on AGN-treated pCM cells. Taken together, pCM cell-based in vitro assay system could be primarily and efficiently applied for evaluating the biofunctional efficacy of various feed additive candidates.


Subject(s)
Angelica/chemistry , Animal Feed , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Food Additives/pharmacology , Gene Expression Regulation, Developmental/drug effects , Gene Expression Regulation, Developmental/genetics , Myoblasts/metabolism , Myoblasts/physiology , Plant Extracts/pharmacology , Animals , Cell Differentiation/genetics , Cell Proliferation/genetics , Cells, Cultured , Chick Embryo , Chickens , Fatty Acids , Glucose/metabolism , Male , Pectoralis Muscles/embryology , Plant Extracts/isolation & purification
18.
Foods ; 7(12)2018 Nov 30.
Article in English | MEDLINE | ID: mdl-30513584

ABSTRACT

The present study was conducted to evaluate the quality and bio-functional properties of Portuguese honeys of different botanical and geographical origins. Quality parameter analyses included the determination of palynological (predominant, secondary, minor and isolated pollen percentage), physicochemical (°Brix, moisture content, pH, electrical conductivity, free acidity, total dissolved solids, salinity, vitamin C content and specific weight) including colour-metrics (CIELAB, Pfund and colour intensity determinations), along with volatile compounds identification using solid phase micro-extraction coupled to gas chromatography mass spectrometry. Bio-activity parameter analysis included the determination of in vitro antioxidant activity and total phenolic content using the 2,2-diphenyl-1-picryl-hydrazyl and Folin-Ciocalteu assays, respectively. Melissopalynological analysis showed that Portuguese honeys were classified as eucalyptus, chestnut and heather, recording significant variations (p < 0.05) among physicochemical, volatile and bio-activity parameter analyses according to both: botanical and geographical origin. Based on the multi-parameter analysis data Portuguese honeys could be characterized by a distinctive colour, a characteristic aroma, whereas conform to the European legislation relating to honey identity and quality. Specific attention should be given in the case of heather honey which showed the highest in vitro antioxidant activity and total phenolic content. Parameters that were also highly correlated using bivariate statistics.

19.
J Biomater Appl ; 32(7): 841-852, 2018 02.
Article in English | MEDLINE | ID: mdl-29187013

ABSTRACT

The development of versatile tubular structures is a subject of broad interest in tissue engineering applications. Herein, we demonstrate the production of tubular structures based on chitosan through a combination of dipping, freeze-drying and supercritical technology approaches. The combination of these techniques yields versatile tubes with a perfectly defined hollow imprint, which upon chemical cross-linking with genipin acquire enhanced mechanical properties (Young Modulus ( E) and ultimate tensile stress (σmax)), as well as improved stability in wet conditions. The biological performance reveals that cells remain attached, well-spread and viable on the surface of cross-linked tubes. As so, is envisioned that our methodology opens up new avenues on tissue engineering approaches, where the design of tubular structures with tuned length, diameter and elasticity is required.


Subject(s)
Biocompatible Materials/chemistry , Chitosan/analogs & derivatives , Cross-Linking Reagents/chemistry , Fibroblasts/cytology , Iridoids/chemistry , Tissue Scaffolds/chemistry , Animals , Cell Line , Elastic Modulus , Freeze Drying , Mice , Tissue Engineering
20.
Biomed Tech (Berl) ; 62(3): 295-306, 2017 May 24.
Article in English | MEDLINE | ID: mdl-27285125

ABSTRACT

This study examined the potential of a new porous calcium hydroxyapatite scaffold covered with poly (lactide-co-glycolide) (PLGA) as a bone substitute, identifying its advantages over Geistlich Bio-Oss®, considered the gold standard, in in vivo biofunctionality investigations. Structural and morphological properties of the new scaffold were analyzed by scanning electron and atomic force microscopy. The biofunctionality assays were performed on New Zealand white rabbits using new scaffold for filling full-thickness defects of critical size. The evaluated parameters were: the presence of macrophages, giant cells, monoocytes, plasma cells, granulocytes, neoangiogenesis, fibroplasia, and the percentage of mineralization. Parallel biofunctionality assays were performed using Geistlich Bio-Oss®. The appearance of bone defects 12 weeks after the new scaffold implantation showed the presence of a small number of typical immune response cells. Furthermore, significantly reduced number of capillary buds, low intensity of fibroplasia and high degree of mineralization in a lamellar pattern indicated that the inflammation process has been almost completely overcome and that the new bone formed was in the final phase of remodeling. All biofunctionality assays proved the new scaffold's suitability as a bone substitute for applications in maxillofacial surgery. It showed numerous biological advantages over Geistlich Bio-Oss® which was reflected mainly as a lower number of giant cells surrounding implanted material and higher degree of mineralization in new formed bone.


Subject(s)
Biocompatible Materials/chemistry , Bone Substitutes/chemistry , Bone and Bones/physiology , Durapatite/chemistry , Minerals/chemistry , Polyesters/chemistry , Polyglactin 910/chemistry , Animals , Bone Substitutes/metabolism , Bone and Bones/chemistry , Porosity , Rabbits
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