Extraction strategies impact the efficiency and nature of extracted compounds. This work assessed the chemical composition and antioxidant capacity of ethanolic, hydroethanolic, and aqueous versus enzyme-assisted extracts (isolated or with the sequential use of alcalase, cellulase, and viscozyme) of the macroalgae (brown, ) and (red, . For both macroalgae, enzyme-assisted extraction (EAE) was the most efficient process compared to solvent-assisted extraction (SAE), independent of solvent.
View Article and Find Full Text PDFCamera traps became the main observational method of a myriad of species over large areas. Data sets from camera traps can be used to describe the patterns and monitor the occupancy, abundance, and richness of wildlife, essential information for conservation in times of rapid climate and land-cover changes. Habitat loss and poaching are responsible for historical population losses of mammals in the Atlantic Forest biodiversity hotspot, especially for medium to large-sized species.
View Article and Find Full Text PDFNature derived compounds represent a valuable source of bioactive molecules with enormous potential. The sea is one of the richest environments, full of skilled organisms, where algae stand out due to their unique characteristics. Marine macroalgae adapt their phenotypic characteristics, such as chemical composition, depending on the environmental conditions where they live.
View Article and Find Full Text PDFThe Caatinga is an exclusively Brazilian biome, and is the largest and most biodiverse Seasonal Tropical Dry Forest in the world. Despite that, the mammalian fauna, especially small mammals, is the least studied of all Brazilian biomes. In order to fill gaps and provide detailed information on small mammals (Didelphimorphia, Rodentia) in the Caatinga biome, we compiled reliable records focusing on richness, composition and some biometric data.
View Article and Find Full Text PDFCalcium plays an important role in barrier function repair and skin homeostasis. In particular, calcium phosphates (CaPs) are well established materials for biomedical engineering due to their biocompatibility. To generate biomaterials with a more complete set of biological properties, previously discarded silk sericin (SS) has been recovered and used as a template to grow CaPs.
View Article and Find Full Text PDFObjective: Intratumor heterogeneity drives cancer progression and therapy resistance. However, it has yet to be determined whether and how subpopulations of cancer cells interact and how this interaction affects the tumour.
Design: We have studied the spontaneous flow of extracellular vesicles (EVs) between subpopulations of cancer cells: cancer stem cells (CSC) and non-stem cancer cells (NSCC).
Aims: Stem cell therapies emerged as treatment modalities with potential to cure neurodegenerative diseases (NDs). However, despite high expectations, their clinical use is still limited. Critical issues in treatment outcomes may be related to stem cells formulation and administration route.
View Article and Find Full Text PDFcross-linked hydrogels have the advantage of effectively fulfilling the wound in its shape and depth. Amongst the new generation of natural-based biopolymers being proposed for wound care and skin regeneration, silk sericin is particularly interesting due to its exceptional properties such as biocompatibility, biodegradability, and antioxidant behavior, among others. In this study, a new enzyme-mediated cross-linked hydrogel composed of silk sericin is proposed for the first time.
View Article and Find Full Text PDFEvery year, worldwide, millions of people suffering from joint pain undergo joint replacement. For most patients, joint arthroplasty reduces pain and improve function, though a small fraction will experience implant failure. One of the main reasons includes prosthetic joint infection (PJI), involving the prosthesis and adjacent tissues.
View Article and Find Full Text PDFSea-derived materials have promising applications in the medical, pharmaceutical, and biotechnological fields. Fish roe, for example, is a highly nutritional product, presenting diverse beneficial effects on human health. Therefore, this work explored extracts of sardine () roe, due to the well-known health benefits of this fish, to produce novel and promising delivery systems.
View Article and Find Full Text PDFInvasion and metastasis correspond to the foremost cause of cancer-related death, and the molecular networks behind these two processes are extremely complex and dependent on the intra- and extracellular conditions along with the prime of the premetastatic niche. Currently, several studies suggest an association between the levels of genes expression and cancer cell invasion and metastasis, which favour the formation of novel tumour masses. The deregulation of genes by HMGA2/TET1 signalling and the regulatory effect of noncoding RNAs generated by the loci can also promote invasion and metastasis, interfering with the expression of genes or other genes relevant to these processes.
View Article and Find Full Text PDFFront Bioeng Biotechnol
February 2020
tissue regeneration can be defined as the implantation of tissue-specific biomaterials (by itself or in combination with cells and/or biomolecules) at the tissue defect, taking advantage of the surrounding microenvironment as a natural bioreactor. Up to now, the structures used were based on particles or gels. However, with the technological progress, the materials' manipulation and processing has become possible, mimicking the damaged tissue directly at the defect site.
View Article and Find Full Text PDFSeaweeds, which have been widely used for human consumption, are considered a potential source of biological compounds, where enzyme-assisted extraction can be an efficient method to obtain multifunctional extracts. Chemical characterization of and extracts obtained by Alcalase and Viscozyme assisted extraction, respectively, showed an increment of macro/micro elements in comparison to the corresponding dry seaweeds, while the ratio of Na/K decreased in both extracts. Galactose, mannose, xylose, fucose, and glucuronic acid were the main monosaccharides (3.
View Article and Find Full Text PDFIn this study, silk fibroin (SF)/poly(ethylene oxide) (PEO) membranes were designed and fabricated by combining ultrasound sonication prior to electrospinning (0 to 20 min) as a strategy to physically control the rheological properties of solutions (10 to 30% w/v PEO) and to improve the spinnability of the system. PEO has proved to be essential as a co-spinning agent to assure good membrane reproducibility and enough flexibility for clinical manipulation. The rheological tests indicated that sonication greatly increased the viscosity of SF/PEO solutions and further enhanced the quality of the produced electrospun fibers with consequent improved mechanical properties in dry and wet conditions.
View Article and Find Full Text PDFDuring the last decade, many cartilage tissue engineering strategies have been developed, being the stem cell-based approach one of the most promising. Transforming Growth Factor-β3 (TGF-β3) and Insulin-like Growth Factor-I (IGF-I) are key proteins involved in the regulation of chondrogenic differentiation. Therefore, these two growth factors (GFs) were immobilized at the surface of a single electrospun nanofibrous mesh (NFM) aiming to differentiate human Bone Marrow-derived Mesenchymal Stem Cells (hBM-MSCs).
View Article and Find Full Text PDFGuided tissue regeneration (GTR) is a surgical procedure applied in the reconstruction of periodontal defects, where an occlusive membrane is used to prevent the fast-growing connective tissue from migrating into the defect. In this work, silk fibroin (SF) membranes were developed for periodontal guided tissue regeneration. Solutions of SF with glycerol (GLY) or polyvinyl alcohol (PVA) where prepared at several weight ratios up to 30%, followed by solvent casting and thermal annealing at 85 °C for periods of 6 and 12 h to produce high flexible and stable membranes.
View Article and Find Full Text PDFPolymeric nanoparticles (NPs) are strong candidates for the development of systemic and targeted drug delivery applications. Their size is a determinant property since it defines the NP-cell interactions, drug loading capacity, and release kinetics. Herein, poly(d,l-lactic acid) (PDLA) NPs were produced by the nanoprecipitation method, in which the influence of type and concentration of surfactant as well as PDLA concentration were assessed.
View Article and Find Full Text PDFMany efforts are being directed worldwide to the treatment of OA-focal lesions. The majority of those efforts comprise either the refinement of surgical techniques or combinations of biomaterials with various autologous cells. Herein, we tested electrospun polycaprolactone (PCL) nanofibrous meshes for cartilage tissue engineering.
View Article and Find Full Text PDFWharton's jelly stem cells (WJSCs) are a potential source of transplantable stem cells in cartilage-regenerative strategies, due to their highly proliferative and multilineage differentiation capacity. We hypothesized that a non-direct co-culture system with human articular chondrocytes (hACs) could enhance the potential chondrogenic phenotype of hWJSCs during the expansion phase compared to those expanded in monoculture conditions. Primary hWJSCs were cultured in the bottom of a multiwell plate separated by a porous transwell membrane insert seeded with hACs.
View Article and Find Full Text PDFThe immobilization of biomolecules at the surface of different biomedical devices has attracted enormous interest in order to enhance their biological functionality at the cellular level. This work aims to develop a biofunctional polymeric substrate capable of selectively binding growth factors (GFs) of interest from a pool of proteins present in a biological fluid: platelet lysate (PL). To achieve this goal, the surface of electrospun PCL nanofibers needs to be activated and functionalized to be able to insert chemical groups for the immobilization of antibodies.
View Article and Find Full Text PDFTo understand the role of chitosan in chitosan-poly(butylene succinate) scaffolds (50% wt), 50%, 25%, and 0% of chitosan were used to produce different scaffolds. These scaffolds were in vitro seeded and cultured with human bone marrow stromal cells in osteogenic conditions, revealing that higher percentage of chitosan showed enhanced cell viability over time, adhesion, proliferation, and osteogenic differentiation. Scaffolds were also implanted in cranial defects and iliac submuscular region in Wistar rats, and the results evidenced that chitosan-containing scaffolds displayed mild inflammatory response and good integration with surrounding tissues, showed by connective tissue colonization and the presence of new blood vessels.
View Article and Find Full Text PDFJ Tissue Eng Regen Med
June 2015
Paracrine signalling from chondrocytes has been reported to increase the synthesis and expression of cartilage extracellular matrix (ECM) by stem cells. The use of conditioned medium obtained from chondrocytes for stimulating stem cells chondrogenic differentiation may be a very interesting alternative for moving into the clinical application of these cells, as chondrocytes could be partially replaced by stem cells for this type of application. In the present study we aimed to achieve chondrogenic differentiation of two different sources of stem cells using conditioned medium, without adding growth factors.
View Article and Find Full Text PDFIndian J Ophthalmol
July 2012
Purpose: To compare the effects of preoperative use of topical anti-inflammatory prednisolone acetate, ketorolac tromethamine, nepafenac and placebo, on the maintenance of intraoperative mydriasis during cataract surgery.
Design: Randomized clinical trial.
Materials And Methods: This single-center, masked, randomized clinical study comprised 140 patients scheduled for cataract surgery.
This study used a rat subcutaneous implantation model to investigate gradual in situ pore formation in a self-regulating degradable chitosan-based material, which comprises lysozyme incorporated into biomimetic calcium phosphate (CaP) coatings at the surface to control the scaffold degradation and subsequent pore formation. Specifically, the in vivo degradation of the scaffolds, the in situ pore formation, and the tissue response were investigated. Chitosan or chitosan/starch scaffolds were studied with and without a CaP coating in the presence or absence of lysozyme for a total of six experimental groups.
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