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Decellularized esophageal matrices are ideal scaffolds for esophageal tissue engineering. Unfortunately, in order to improve transplantation possibilities, they require modification to reduce their degradation rate and immunogenicity. To date, no modifying agent has been approved to overcome these limitations. The objective of this study was to evaluate the ability of silver nanoparticles (AgNPs) to improve the structural stability and biocompatibility of decellularized rat esophagi. AgNPs have the advantage over currently used agents in that they bind with collagen fibers in a highly ordered manner, via non-covalent binding mechanisms forming multiple binding sites, while other agents provide only two-point connections between collagen molecules. Rat esophagi were decellularized, loaded with 5 μg/mL of AgNPs (100 nm), and then treated with an immobilization-complex buffer composed of ethyl carbodiimide hydrochloride and N-hydroxysuccinimide (EDC/NHS). Then, they were evaluated in terms of ultra-structural morphology, water uptake, in vitro resistance to enzymatic and thermal degradation, indentation strength, in vitro anti-calcification, cytocompatibility with rat bone marrow derived stromal cells (rat-BMSCs), angiogenic properties, and in vivo biocompatibility, and compared to scaffolds modified using glutaraldehyde and EDC/NHS complex buffer alone. AgNP-modified scaffolds showed an improved ultrastructure, good water uptake, and considerable resistance against in vitro degradation and indentation, and a high resistance against in vitro calcification. Moreover, they were cytocompatible for allogeneic rat-BMSCs. Additionally, AgNPs did not alter the angiogenic properties of the modified scaffolds and decreased host immune responses after their subcutaneous implantation. The structural properties and biocompatibility of decellularized esophageal matrices could be improved by conjugation with AgNPs.

Decellularized esophageal matrices are ideal scaffolds for esophageal tissue engineering. Unfortunately, in order to improve transplantation possibilities, they require modification to reduce their degradation rate and immunogenicity. To date, no modifying agent has been approved to overcome these limitations. The objective of this study was to evaluate the ability of silver nanoparticles (AgNPs) to improve the structural stability and biocompatibility of decellularized rat esophagi. AgNPs have the advantage over currently used agents in that they bind with collagen fibers in a highly ordered manner, via non-covalent binding mechanisms forming multiple binding sites, while other agents provide only two-point connections between collagen molecules. Rat esophagi were decellularized, loaded with 5 μg/mL of AgNPs (100 nm), and then treated with an immobilization-complex buffer composed of ethyl carbodiimide hydrochloride and N-hydroxysuccinimide (EDC/NHS). Then, they were evaluated in terms of ultra-structural morphology, water uptake, in vitro resistance to enzymatic and thermal degradation, indentation strength, in vitro anti-calcification, cytocompatibility with rat bone marrow derived stromal cells (rat-BMSCs), angiogenic properties, and in vivo biocompatibility, and compared to scaffolds modified using glutaraldehyde and EDC/NHS complex buffer alone. AgNP-modified scaffolds showed an improved ultrastructure, good water uptake, and considerable resistance against in vitro degradation and indentation, and a high resistance against in vitro calcification. Moreover, they were cytocompatible for allogeneic rat-BMSCs. Additionally, AgNPs did not alter the angiogenic properties of the modified scaffolds and decreased host immune responses after their subcutaneous implantation. The structural properties and biocompatibility of decellularized esophageal matrices could be improved by conjugation with AgNPs.

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Acute liver failure (ALF) occurs due to severe liver damage that triggers rapid loss of normal liver function. Here, we investigate the usefulness of an injectable liver extracellular matrix (LECM)–rich hydrogel generated from an optimized decellularization protocol incorporated with silver nanoparticles (AgNPs) as a promising therapy for ALF. First, we optimized a non‐destructive protocol for rat liver decellularization to obtain ECM‐rich well‐preserved scaffold. Then, LECM hydrogel generated from two commonly used decellularization protocols were compared by LECM hydrogel obtained from our optimized protocol. The ALF model was induced by an intraperitoneal (IP) thioacetamide (TAA) injection followed by the IP injection of LECM hydrogel, collagen‐AgNPs mixture or LECM hydrogel‐AgNPs mixture. LECM‐rich scaffold and hydrogel were successfully obtained using our optimized decellularization protocol. Use of the LECM hydrogel‐AgNPs mixture to treat TAA induced ALF, greatly improving liver injury and histological liver regeneration. Interleukin‐6 (IL‐6) and transforming growth factor beta ( TGF‐β) expressions were significantly reduced, while albumin, hepatocyte growth factor, and Ki67‐positive cells were highly expressed. Moreover, aspartate transaminase (AST) and alanine transaminase (ALT) plasma levels, and liver homogenate nitric oxide (NO) level were significantly lowered. In conclusion, the LECM hydrogel‐AgNPs mixture has potential efficient therapeutic and regenerative effects on TAA‐induced liver injury. This article is protected by copyright. All rights reserved.

Acute liver failure (ALF) occurs due to severe liver damage that triggers rapid loss of normal liver function. Here, we investigate the usefulness of an injectable liver extracellular matrix (LECM)–rich hydrogel generated from an optimized decellularization protocol incorporated with silver nanoparticles (AgNPs) as a promising therapy for ALF. First, we optimized a non‐destructive protocol for rat liver decellularization to obtain ECM‐rich well‐preserved scaffold. Then, LECM hydrogel generated from two commonly used decellularization protocols were compared by LECM hydrogel obtained from our optimized protocol. The ALF model was induced by an intraperitoneal (IP) thioacetamide (TAA) injection followed by the IP injection of LECM hydrogel, collagen‐AgNPs mixture or LECM hydrogel‐AgNPs mixture. LECM‐rich scaffold and hydrogel were successfully obtained using our optimized decellularization protocol. Use of the LECM hydrogel‐AgNPs mixture to treat TAA induced ALF, greatly improving liver injury and histological liver regeneration. Interleukin‐6 (IL‐6) and transforming growth factor beta ( TGF‐β) expressions were significantly reduced, while albumin, hepatocyte growth factor, and Ki67‐positive cells were highly expressed. Moreover, aspartate transaminase (AST) and alanine transaminase (ALT) plasma levels, and liver homogenate nitric oxide (NO) level were significantly lowered. In conclusion, the LECM hydrogel‐AgNPs mixture has potential efficient therapeutic and regenerative effects on TAA‐induced liver injury. This article is protected by copyright. All rights reserved.

Teeth extraction is inevitable in the case of progressive or alveolar bone destructing chronic periodontitis. Unfortunately, the resulting bone defects may lead to many side effects. Here, we developed a novel dental-bone substitute to preserve the extraction socket for hemostasis and bone regeneration. Hyaluronic acid-gelatin hydrogel (HG) polymers, β-tricalcium phosphate (TCP), and biphasic calcium phosphate (BCP) ceramics were fabricated using freeze-drying methods. The HG/TCP/BCP plug was prepared to be easily applied by pouring the mixture of HG and TCP into the shell-shaped mold, followed by placing the sponge type of BCP in the core portion of the mold compared to HG/TCP and collagen plugs. In vitro studies showed that HG/TCP and HG/TCP/BCP plugs were cytocompatible and could promote osteogenesis by upregulating the expressions of bone-related genes COL1, RUNX2, ALP, and OPN. The rabbit-femur defect model revealed that the implanted HG/TCP/BCP plug, which showed excellent hemostatic property, promote bone regeneration with a high rate of collagen distribution along with ALP and OPN expressions more than could the HG/TCP plug at 3 months after implantation, whereas the collagen plugs just filled with chondrocytes for cartilages formation. The HG/TCP/BCP plug should be considered for potential dental applications for one-step socket preservation.

In river Nile and its branches, numerous individuals of red swamp crayfish, Procambarus clarkii, displayed melanised areas in gills. To clarify the cause of these lesions, several isolates of Fusarium spp. were recovered. The fungi were first identified morphologically on culture media. Subsequently, molecular identification was carried out based on the internal transcribed spacer (ITS) region and beta-tubulin gene (TUB2) sequences. Based on GenBank database searches, the causative agent was identified as Fusarium solani. To fulfill Koch`s postulates, an experimental infection was induced using a representative isolate (ESHA-1). The challenged crayfish showed similar lesions noticed on naturally-infected ones, and the pathogen was re-isolated from the lesions of the infected individuals. Zinc oxide nanoparticles (ZnO NPs) exhibited a significant reduction in fungal growth. To our knowledge, this is the first record of Fusarium solani infection in red swamp crayfish inhabiting the River Nile.

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