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Biomaterials represent a distinct class of materials used in various medical applications, such as replicating the shape or function of damaged tissue caused by disease or trauma. The increasing focus on polyhydroxyalkanoate (PHA) research can be attributed to their properties, such as biodegradability, biocompatibility, and bioresorbability. PHAs can be incorporated into polymeric complexes or combined with bioceramics or bioactive substances. Films of PHO-HAp-Curcumin were prepared, and optimization studies were conducted using Design-Expert software (Stat-Ease 360-Trial Version). The effects of independent variables (amount of PHO, HAp, and curcumin) on biodegradability, film thickness, and curcumin release were studied. Statistical modeling revealed significant interactions among the components, with the 2FI and quadratic models providing strong predictive accuracy. The interaction of HAp and PHO amounts (X2X3) has a significant effect on biodegradability (Y1) and film thickness (Y3). For the degree of the cumulative release of curcumin (CDR), there was no significant interaction between the independent variables (curcumin-X1, HAp-X2, and PHO-X3). Optimized film exhibited a maximum desirability of 0.777 with 1 mg of curcumin, 100 mg of HAp, and 172.31 mg of PHO. A morphological analysis of optimized film revealed a rough, particle-rich surface favorable for biomedical use. The findings highlight the promise of PHO-HAp-Curcumin composite films in advancing tissue engineering.

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Biomaterials represent a distinct class of materials used in various medical applications, such as replicating the shape or function of damaged tissue caused by disease or trauma. The increasing focus on polyhydroxyalkanoate (PHA) research can be attributed to their properties, such as biodegradability, biocompatibility, and bioresorbability. PHAs can be incorporated into polymeric complexes or combined with bioceramics or bioactive substances. Films of PHO-HAp-Curcumin were prepared, and optimization studies were conducted using Design-Expert software (Stat-Ease 360-Trial Version). The effects of independent variables (amount of PHO, HAp, and curcumin) on biodegradability, film thickness, and curcumin release were studied. Statistical modeling revealed significant interactions among the components, with the 2FI and quadratic models providing strong predictive accuracy. The interaction of HAp and PHO amounts (X2X3) has a significant effect on biodegradability (Y1) and film thickness (Y3). For the degree of the cumulative release of curcumin (CDR), there was no significant interaction between the independent variables (curcumin-X1, HAp-X2, and PHO-X3). Optimized film exhibited a maximum desirability of 0.777 with 1 mg of curcumin, 100 mg of HAp, and 172.31 mg of PHO. A morphological analysis of optimized film revealed a rough, particle-rich surface favorable for biomedical use. The findings highlight the promise of PHO-HAp-Curcumin composite films in advancing tissue engineering. © 2025 by the authors.

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Marine glycosaminoglycans (GAG) isolated from different invertebrates, such as molluscs, starfish or jellyfish, have been described as unique molecules with important pharmacological applications. Scarce information is available on GAG extract from Rapana venosa marine snail. The aim of this study was to isolate a GAG extract from R. venosa marine snail and to investigate its physicochemical, antioxidant and antiproliferative properties for further biomedical use. The morphology, chemical and elemental composition of the extract were established as well as the sulfate content and N- to O-sulfation ratio. Fourier transform infrared (FTIR) spectra indicated that GAG extract presented similar structural characteristics to bovine heparan sulfate and chondroitin sulfate. The pattern of extract migration in agarose gel electrophoresis and specific digestion with chondroitinase ABC and heparinase III indicated the presence of a mixture of chondroitin sulfate-type GAG, as main component, and heparan sulfate-type GAG. Free radical scavenging and ferric ion reducing assays showed that GAG extract had high antioxidant activity, which slightly decreased after enzymatic treatment. In vitro MTT and Live/Dead assays showed that GAG extract had the ability to inhibit cell proliferation in human Hep-2 cell cultures, at cytocompatible concentrations in normal NCTC clone L929 fibroblasts. This capacity decreased after enzymatic digestion, in accordance to the antioxidant activity of the products. Tumoral cell migration was also inhibited by GAG extract and its digestion products. Overall, GAG extract from R. venosa marine snail exhibited antioxidant and antiproliferative activities, suggesting its potential use as novel bioactive compound for biomedical applications.

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Bacterial cellulose is a biocompatible biomaterial with a unique macromolecular structure. Unlike plant-derived cellulose, bacterial cellulose is produced by certain bacteria, resulting in a sustainable material consisting of self-assembled nanostructured fibers with high crystallinity. Due to its purity, bacterial cellulose is appealing for biomedical applications and has raised increasing interest, particularly in the context of 3D printing for tissue engineering and regenerative medicine applications. Bacterial cellulose can serve as an excellent bioink in 3D printing, due to its biocompatibility, biodegradability, and ability to mimic the collagen fibrils from the extracellular matrix (ECM) of connective tissues. Its nanofibrillar structure provides a suitable scaffold for cell attachment, proliferation, and differentiation, crucial for tissue regeneration. Moreover, its mechanical strength and flexibility allow for the precise printing of complex tissue structures. Bacterial cellulose itself has no antimicrobial activity, but due to its ideal structure, it serves as matrix for other bioactive molecules, resulting in a hybrid product with antimicrobial properties, particularly advantageous in the management of chronic wounds healing process. Overall, this unique combination of properties makes bacterial cellulose a promising material for manufacturing hydrogels and 3D-printed scaffolds, advancing the field of tissue engineering and regenerative medicine.

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Background: The force a muscle exerts is partly determined by anatomical parameters, such as its physiological cross-section. The temporal muscle is structurally heterogeneous. To the authors' knowledge, the ultrastructure of this muscle has been poorly specifically studied.Methods: Five adult Wistar rats weighting 350-400 g were used as temporal muscle donors. Tissues were specifically processed and studied under transmission electron microscope.Results: On ultrathin cuts, the general ultrastructural pattern of striated muscles was observed. Moreover, pennate sarcomeres were identified, sharing a one-end insertion on the same Z-disc. Bipennate morphologies resulted when two neighbor sarcomeres, attached on different neighbor Z-discs and separated at that end by a triad, converged to the same Z-disc at the opposite ends, thus building a thicker myofibril distinctively flanked by triads. Tripennate morphologies were identified when sarcomeres from three different Z-discs converged to the same Z-disc at the opposite ends.Conclusions: These results support recent evidence of sarcomeres branching gathered in mice. Adequate identification of the sites of excitation-contraction coupling should be on both sides of a myofibril, on bidimensional ultrathin cuts, to avoid false positive results due to putative longitudinal folds of myofibrils.& COPY; 2023 Elsevier GmbH. All rights reserved.

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Background and Objectives: The dental pulp stem cells are highly proliferative and can differentiate into various cell types, including endothelial cells. We aimed to evaluate the ultrastructural characteristics of the human dental pulp cells of the permanent frontal teeth. Materials and Methods: Human adult bioptic dental pulp was collected from n = 10 healthy frontal teeth of five adult patients, prior to prosthetic treatments for aesthetic purposes. Tissues were examined under transmission electron microscopy. Results: We identified cells with a peculiar trait: giant nucleoli resembling intranuclear endoplasmic reticulum, which mimicked extrusion towards the cytoplasm. These were either partly embedded within the nuclei, the case in which their adnuclear side was coated by marginal heterochromatin and the abnuclear side was coated by a thin rim of ribosomes, or were apparently isolated from the nuclei, while still being covered by ribosomes. Conclusions: Similar electron microscopy features were previously reported in the human endometrium, as nucleolar channel system; or R-Rings induced by Nopp140. To our knowledge, this is the first report of extruded nucleolar structure in the dental pulp. Moreover, the aspect of giant extruded nucleoli was not previously reported in any human cell type, although similar evidence was gathered in other species as well as in plants.