Objectives: The aim of this study was to develop functionalized scaffold for incisional hernia regeneration. New composite scaffolds, based on polypropylene chirurgical mesh (PP), poly-e-caprolactone ...(PCL) nanofibres, and thrombocyte-rich solution (TRS) have been prepared and tested in in vitro study using 3T3 fibroblasts. Methods: Four different samples have been prepared: PP, PP covered with PCL nanofibres (PP+PCL), as well as PP and PP+PCL functionalized with immobilized thrombocytes (PP+TRS and PP+PCL+TRS, respectively). Nanofibres were prepared by the electrospinning method from the chlorophorm/ethanol solution. To achieve thrombocyte immobilization, PCL nanofibres were immersed in a thrombocyte-rich solution for 2 hours. 1x10 super(3) 3T3 fibroblast were seeded onto each scaffold and cultured for 14 days. Cell proliferation and viability were evaluated on the day 1, 3, 7, 10, and 14 by MTT assay and live/dead stainig (BCECF- AM and Propidium iodide) with subsequent confocal microscopy visualization. Results: Biocompatibility of functionalized surgical mesh, cell proliferation and viability were determined using MTT test and confocal microscopy. The regenerative potential of thrombocytes was based on the release of growth factors that occurs when thrombocytes rupture. MTT test demonstrates significant increase in cell number on scaffold covered with PCL and functionalized with immobilized thrombocytes. These results correlated well with live/dead staining. Viability of cells 14 days after seeding was 95%. Conclusions: Polypropylene surgical mesh was covered with PCL nanofibre layer, functionalized with immobilized thrombocytes and seeded with 3T3 fibroblasts. Cells proliferated well on the functionalized scaffold during a 14-day experiment. Very good biocompatible properties of this scaffold were observed. This matirial will be tested and has a good potential to be clinically used.
Objectives: Objective of this work is to provide a new and more sensitive method based on RT-qPCR (quantitative polymerase chain reaction) for biocompatibility testing in order to facilitate further ...improvements of dialysis filter devices. Need for improved biocompatibility is given by the clinical observation that dialysis patients have increased risk of cardiovascular disease that is suspected to be influenced by the foreign surface contact. Although there exist a couple of methods to measure biocompatibility, these methods are not sensitive enough to differentiate biocompatibility of modern filter devices and consequently these methods are not suited to guide future developments. Methods: The method is a two-step in vitro process. The first part is the exposure of human blood in parallel to two dialysis filter devices. The second part is the quantitative analysis of the activation level of the leukocyte cell population. The activation level is quantified by the amount of mRNA of a specified set of inflammatory markers by real-time quantitative PCR. Additional information is obtained by FACS analysis of surface marker proteins. Results: RT-qPCR analysis of inflammatory markers in human blood showed that exposure of blood to different filter devices resulted in different leukocyte activation levels. Particularly early inflammatory markers like TNF- alpha and IL-1 beta revealed statistically significant differences between filter devices. Though physical and chemical analysis of the filter materials showed differences in filter materials, no single parameter could be correlated to increased leukocyte activation. Conclusions: A new method based on RT-qPCR could be established for biocompatibility testing of modern dialysis filter devices. The method allows in vitro characterization of inflammatory processes that are caused by foreign surface contact and are suspected to be clinically relevant for cardiovascular complications. Moreover, the method showed differences in leukocyte activation between commercial dialysis filters and is therefore suited to guide further improvements in biocompatibility.
Objectives: There is a rising interest for the development of small-sized blood vessels substitutes. Several studies have been focused on the development of a biodegradable graft temporarily able to ...substitute the blood vessels and allow their complete regeneration after a certain time. We tried to develop a biodegradable material, with optimal mechanical characteristics and the capacity to allow cells adhesion, differentiation and proliferation by electrospinning to obtain a nano-fibrillar scaffold starting from a polymeric solution. Methods: We report the in vivo application on rats of two new electrospun biodegradable materials, specifically designed to create tubular structures. Both biomaterials can be functionaiized with several polypeptidic and non-polypeptidic active molecules (growth factors or drugs). In one case PHEA-PLA was co-spun with silk fibroin (Fibro-PHEA-PLA) by a parallel electrospinning process to obtain a scaffold with two different polymeric fibers. In the other case, PHEA-PLA was mixed with polycaprolactone (PCL-PHEA-PLA) to obtain a single spinning solution for the obtainment of hybrid fibers scaffold. The in vitro assay showed colonization by fibroblasts in both materials. The scaffolds were implanted in a dorsal fascial pouch on Winstar rats to evaluate their in vivo biocompatibility and tissue integration. The scaffolds were removed at 7, 15 and 40 days after implantation. Results: The pathological findings showed that both materials were totally absorbed after 40 days without any sign of inflammation. A neutrophilic reaction was predominant at 7 days, especially for PCL-PHEA-PLA alone, whereas a lymphocytic invasion was showed at 15. At 15 days Fibro-PHEA-PLA showed a good cell adhesion with a low grade of inflammation. Cell adhesion was confirmed at SEM scan. Conclusions: This preliminary study showed a good biocompatibility property of the scaffolds that needs of further investigations. The capability of the materials to be functionaiized, should allow us to guide the development of bioengineered vessels.
Objectives: State of the art biocompatible and biodegradable poly(lactic acid) (PLA) has several disadvantages including bulk erosion mechanism, fast loss of mechanical properties, spontaneous ...release of acidic compounds and the inability to be structured by high resolution Additive Manufacturing Techniques (AMT). It was the aim of the current project to provide low toxic photopolymerizable formulations that can be printed by AMT to form 3D cellular scaffolds for bone tissue engineering with good biocompatibllity and biodegradability. Methods: Currently, most of the used photopolymers for AMT are based on (meth)acrylates. Beside the considerable irritancy and sometimes cytotoxicity of acrylate-based monomers, the formation of high molecular polyacrylic acid through hydrolytic degradation of the polymer is another undesirable aspect of these materials when applied to the biomedical field. Therefore, photopolymers based on vinylesters and vinylcarbonates as polymerizable group, which are FDA approved, low molecular and water-soluble poly(vinyl alcohol) upon hydrolytic degradation, were evaluated. Several monomers based on different substrates were synthesized to examine their cytotoxicity, photoreactivity, mechanical properties and degradation behavior. In vivo experiments of 3D-parts were carried out in New Zealand White Rabbits. Results: In vitro studies with osteoblast-like cells, showed by far lower cytotoxicity than for their (meth)acrylate-based counterparts. By application of hydroxyapatite as filler mechanical properties already approached values from that of natural bone. The degradation behavior of the new polymers can be easily tuned between several months and years. In vivo studies showed excellent biocompatibility and osteoconductivity of the new materials. Conclusions: It has been proven that the new generation of polymers have outstanding properties for the application in the biomedical field. Beside low cytotoxicity of monomers, polymers and degradation products, the polymers have tuneable mechanical properties. Furthermore, the degradation behavior can be tuned over a broad range and advantageous surface erosion mechanism (absence of acidic degradation products) can be seen.
Objectives: Calcium phosphate ceramics are popular materials for bone reconstruction and reinforcement for a long time. Hydroxyapatite (HA), one of the calcium phosphate ceramics, has been ...successfully applied in medicine due to its excellent biocompatibility with hard tissues. Since its chemical and crystallographic properties closely resemble those of bone and tooth minerals, HA attracts a particular interest for bone grafting, augmentation in maxillofacial surgery and in orthopedics as space filling material. There is limited literature information on using bovine enamel as graft material. Moreover, there are still no attempts to use sheep enamel (and dentine) HA as a graft material. The aim of this study was to investigate the structure and the mechanical properties of bioceramics from sheep derived enamel HA. Methods: Bovine teeth were collected and cleaned from fatty tissues. Then they were subjected to calcination at ca. 850 degree C. Enamel and dentine parts were separated easily. Enamel parts were wet ball milled until fine powder (100 mu m) was produced. The dried powders were dry pressed to cylindrical green samples, suitable for compression test. The samples were sintered for 4-hours In air at several temperatures between 1000 degree C-1300 degree C. Microhardness, compression strength and density measurements along with X-ray diffraction analysis and SEM observations of the sintered samples and statistical-tests were realized. Results: The best values for compression strength and microhardness were obtained for the samples sintered at 1300 degree C, namely 100.17MPa and 368.36HV, respectively. These results agree fairly well with the density measurements as well as the crystallographic analysis and the microstructure observations. Conclusions: The comparison of the results of this study with those obtained from earlier studies where HA was derived from bovine bones (BHA) or BHA composites shows that the sheep derived enamel HA results in superb biomaterials. Moreover, this study proposes a production of HA from an economic and natural source.
Multiomics‐driven elucidation of RBS‐10 as a prodrug bioactivated by the enzyme NQO1 is reported by Antoni Riera, Cristina Mayor‐Ruiz et al. in their Research Article (e202316730). RBS‐10 shows ...preferential cytotoxicity against cancer cells pan‐resistant to degraders.
The objective of this study is to evaluate the in vitro and in vivo degradation profile and biocompatibility of poly-L-lactic acid (PLLA) porous microspheres (PMs) for their potential application as ...injectable microcarrier or micro-scaffolds materials in the research and clinical use of craniofacial cartilage repair. In this study, PLLA PMs prepared exhibited spherical shape and uniform surface pores followed by 24-week evaluations for degradation behavior and biocompatibility. In vitro degradation analysis encompassed morphological examination, pH monitoring, molecular weight analysis, thermodynamic assessment, and chemical structure analysis. After 12 weeks of in vitro degradation, PMs maintained a regular porous spherical structure. Molecular weight and glass transition temperature of PLLA PMs decreased over time, accompanying with an initial increase and subsequent decrease in crystallinity. Enzymatic degradation caused morphological changes and accelerated degradation in the in vitro studies. Finally, in vivo evaluations involved subcutaneous implantation of PLLA PMs in rats, demonstrating biocompatibility by enhancing type I and type III collagen regeneration as observed in histological analysis. The results demonstrated that PLLA PMs were able to maintain their spherical structure for 12 weeks, promoting the generation of collagen at the implantation site, meeting the time requirements for craniofacial cartilage repair.
Nanocellulose (NC) has lately appeared as a member of the major promising “green” materials, garnering great attentiveness due to it’s unique features. Several new materials with huge variety of ...biomedical uses have been developed based on the most coveted aspects of Nanocellulose, including biodegradability, sustainability, biocompatibility and their especial physicochemical properties. There are primarily three class of Nanocellulose, every one of which is maufactured in a different way and has different qualities. In the previous couple of years, scientists have concentrated on nanocellulose-based systems which are employed as drug delivery vehicles. Controlled and sustained drug release has varying potential for different applications and administration routes; in this case, nanocellulose was used as a persistent biomaterial that aided in drug delivery. There are two different forms of nanocellulose-based biomedical materials that are currently being developed. At the molecular level, they are tissue bioscaffolds for cellular growth, drug excipients for drug administration, and enzyme/protein immobilisation and recognition. On the contrary at the macroscopic level biomaterial, they are blood vascular and soft tissue substitutes, skin and bone tissue healing materials, and antibacterial materials. The prospective biomedical use of nanocellulose will also be determined by its functional alteration.
•Nanocellulose – Mainly Introduction, Production methods, Properties and applications.
Nanoparticle-based therapies are found to be effective due to the unique mechanisms-of-action to engineered nanoparticles. These nanoparticles are programmed to be target specific and they can hold ...drugs along with imaging agents for simultaneous diagnostic and therapeutic purposes. They are making their way into the clinical realm. In this work we propose to develop Cadmium sulphide (CdS) nanoparticles with reduced toxicity that could function as a theranostic nanoparticle for bio- imaging applications. The work focuses on the toxicological investigation of surface modified cadmium sulphide nanoparticles. Uncoated and Chitosan coated CdS nanoparticles were synthesized by wet chemical method. The physico-chemical properties of the nanoparticles were characterized by X-ray diffraction, UV–Vis absorption, Fourier transform infrared, photoluminescence, X-ray photoelectron spectroscopy, dynamic light scattering, zeta potential and transmission electron microscopy. MTT assay was performed for toxicity profiling of the synthesized CdS nanoparticles in Human Jurkat cell and erythrocytes cell lines. The results showed a significant reduction in toxicity when the CdS nanoparticles surface was modified with Chitosan. Flow cytometer studies were performed to assess the incorporation of the synthesized nanoparticles into the cells. Photoluminescence studies showed that the surface modified CdS nanoparticles retained their fluorescence intensity regardless of their surface modification with Chitosan. Chitosan modified surface of the nanoparticles served as an effective barricade against the degradation of cadmium core. Surface modification with Chitosan, reduced the toxicity of cadmium sulphide nanoparticles retaining their fluorescent property in the cells. Thus by intentionally attaching bio-conjugates can be efficiently used for drug delivery to target specific cells as well as enable the imaging for cells.
•Chitosan coating preserves the integrity and stability of the CdS NPs.•Surface modification with chitosan showed a significant reduction in the toxicity of CdS NPs.•Chitosan modified surface served as an effective safeguard against the degradation of cadmium ions.•Chitosan coated CdS NPs can serve as an effective theranostics probe for bio-imaging.
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