Fabrication and characterization of 3D printing scaffold technology by extract oils from plant and its applications in the cardiovascular blood

Extract oils from plants used in 3D polysaccharides modified with natural protein polymer modified polymer scaffolds can help to reduce blood pressure. This study aimed to use extract oils from plant (EOP)as blood pressure-reducing, bind them to magnetic iron nanoparticles (Fe3O4@NPs), then bind them to polymeric 3D print scaffolds [chitosan, polylactic acid, and polyurethane (CS/PLA/PU), modified with natural protein and finally separate them. This method made it possible to investigate different variables for nanoparticles. In this project, synthesis polymer, modified gelatin (Mo-Ge), PEGylation, extract oils from plant loading and release process in nanocarrier with different concentrations were examined and cell proliferation was optimized. The results show that 75% of the extract oils from plant loaded on iron magnetic nanoparticles containing PEGylated polymer scaffolds was released. Cell proliferation was performed for the sample. In this process, modification of scaffolding with polysaccharides modified with natural protein and extract oils from plant increased the efficiency of nanoparticles among the studied Allium sativum and Zingiber officinale. The size of A. sativum and Z. officinale were 29.833 nm and 150.02 nm size, respectively. These behaved very similarly to each other and A. sativum had the biggest effect in lowering blood pressure. The application of extract oils from plant in 3D mode scaffolding has not been studied before and this is the first analysis to do so, using nanoparticles.

Advances in Skin Wound and Scar Repair by Polymer Scaffolds

Scars, as the result of abnormal wound-healing response after skin injury, may lead to loss of aesthetics and physical dysfunction. Current clinical strategies, such as surgical excision, laser treatment, and drug application, provide late remedies for scarring, yet it is difficult to eliminate scars. In this review, the functions, roles of multiple polymer scaffolds in wound healing and scar inhibition are explored. Polysaccharide and protein scaffolds, an analog of extracellular matrix, act as templates for cell adhesion and migration, differentiation to facilitate wound reconstruction and limit scarring. Stem cell-seeded scaffolds and growth factors-loaded scaffolds offer significant bioactive substances to improve the wound healing process. Special emphasis is placed on scaffolds that continuously release oxygen, which greatly accelerates the vascularization process and ensures graft survival, providing convincing theoretical support and great promise for scarless healing.

Impact of statins on vascular scaffolds response in porcine carotid arteries

Surgical treatments of arterial occlusive disease with fully absorbable polymeric scaffolds, as a potential alternative to permanent metallic stents, are increasingly penetrating the clinical field. An addition part of the management of patients suffering from vascular diseases is the administration of statins. In this study, absorbable x-ray marked PLLA-based polymer scaffolds and permanent bare-metal stents (BMS) were implanted interventionally into both common carotid arteries (CCA) of 6 healthy female pigs via the left common iliac artery (8F-sheath). The pigs were administered dual antiplatelet drugs oral starting 3 days before the procedure until the end of the study. In Addition, the pigs received atorvastatin orally, beginning 5 days prior to surgery and lasting until the study ended. Stented CCA segments were explanted after 4 weeks, and processed for quantitative histomorphometry, and estimation of vascular inflammation and injury scores. Polymer scaffolds showed a decreased residual lumen area and higher stenosis after 4 weeks (6.41 ± 0.83 mm² and 40.52 ± 5.01%) as compared to the bare-metal reference stent (15.17 ± 0.896 mm² and 7.80 ± 0.88%). After 4 weeks, inflammation score were higher in the polymer group (1.30 ± 0.37) compared to the BMS group (0.42 ± 0.18). In contrast, the BMS showed a slightly elevated vascular injury score (0.85 ± 0.12), as compared to the polymer (0.60 ± 0.23) group. In this preclinical model, the new absorbable polymeric scaffolds showed similar technical feasibility and safety for vascular application as the permanent metal stents. Although no positive trends were observed with oral treatment with atorvastatin, further optimization with a dual-loaded coating is still reasonable. In addition, reduced strut thickness of the polymer scaffolds would have potential to positively impact tissue ingrowth between struts and should be considered in future work on stent design.

Electrospun fibre diameter and its effects on vascular smooth muscle cells

Bypass grafting is a technique used in the treatment of vascular disease, which is currently the leading cause of mortality worldwide. While technology has moved forward over the years, synthetic grafts still show significantly lower rates of patency in small diameter bypass operations compared to the gold standard (autologous vessel grafts). Scaffold morphology plays an important role in vascular smooth muscle cell (VSMC) performance, with studies showing how fibre alignment and surface roughness can modulate phenotypic and genotypic changes. Herein, this study has looked at how the fibre diameter of electrospun polymer scaffolds can affect the performance of seeded VSMCs. Four different scaffolds were electrospun with increasing fibre sizes ranging from 0.75 to 6 µm. Culturing VSMCs on the smallest fibre diameter (0.75 µm) lead to a significant increase in cell viability after 12 days of culture. Furthermore, interesting trends were noted in the expression of two key phenotypic genes associated with mature smooth muscle cell contractility (myocardin and smooth muscle alpha-actin 1), whereby reducing the fibre diameter lead to relative upregulations compared to the larger fibre diameters. These results showed that the smallest (0.75 µm) fibre diameter may be best suited for the culture of VSMCs with the aim of increasing cell proliferation and aiding cell maturity.

Polymer Scaffolds-Enhanced Bone Regeneration in Osteonecrosis Therapy

Osteonecrosis without effective early treatment eventually leads to the collapse of the articular surface and causes arthritis. For the early stages of osteonecrosis, core decompression combined with bone grafting, is a procedure worthy of attention and clinical trial. And the study of bone graft substitutes has become a hot topic in the area of osteonecrosis research. In recent years, polymers have received more attention than other materials due to their excellent performance. However, because of the harsh microenvironment in osteonecrosis, pure polymers may not meet the stringent requirements of osteonecrosis research. The combined application of polymers and various other substances makes up for the shortcomings of polymers, and to meet a broad range of requirements for application in osteonecrosis therapy. This review focuses on various applying polymers in osteonecrosis therapy, then discusses the development of biofunctionalized composite polymers based on the polymers combined with different bioactive substances. At the end, we discuss their prospects for translation to clinical practice.