Electrospun Fibers as A Wound Dressing Material using Combination of Cellulose Acetate/Collagen Seeding Stem Cell

Wound healing is a complex tissue regeneration process that the body undergoes as a response to wound openings or missing cellular structures as a result of various types of traumatic injury. Because of the ability of materials to induce a high immune response or limited donor tissues, the skin repair and regeneration methods using allografts and autografts cannot be widely used. Many researches have shifted into tissue engineering approaches using scaffolds. To achieve the goal of tissue reconstruction, scaffolds must meet some specific requirements include biocompatibility, biodegradability, and mechanical properties. Our study aimed to fabricate composite cellulose acetate-collagen (CA/Collagen) scaffolds by electrospinning and determine the appropriate compositions of CA:Collagen for obtaining skin substitutes as wound dressing through investigating the morphological of stem cell seeded on electrospun CA/Collagen membranes. High proliferation of mesenchymal stem cells on electrospun CA/collagen 75:25 (wt.%) confirmed the capability of CA/collagen 75:25 nanofibers as a tissue-engineered scaffold, while the electrospun CA/collagen 75:25 can be a potential low-adherent wound dressing

Injectable Bone Substitute Paste Based on Hydroxyapatite, Gelatin and Streptomycin for Spinal Tuberculosis

World Health Organization (WHO) in 2005 reported that cases of tuberculosis (TB) in the world occur more than 8 million annually and 5-10% was attacked in spine. The most effective treatment of spinal TB is evacuation of infected bone segments and fills with bone graft. It has been synthesized and characterized of Injectable Bone Substitute (IBS) paste based on hydroxyapatite, gelatin and streptomycin. IBS paste synthesized by mixing hydroxyapatite and gelatin 20% w/v with 75:25, 70:30, 65:35 and 60:40 ratio and streptomycin 10 wt%. The mixture was then added with hydroxypropyl methylcellulose (HPMC) 4% w/v as suspending agent. In vitro characterization performed includes acidity (pH), injectability test, setting time, cytotoxicity (MTT assay) and microbacterium test. Acidity test results indicate a fourth variation of the samples had pH values approaching normal body pH (7.3 to 7.6) and is able to maintain stability when measured in 7 days. Injectability test results indicate IBS paste is injectable with the highest percentage of the injectability value at 97.74% ± 0.19%. IBS paste has been setting within 30 minutes to 1 hour when injected on hydroxyapatite scaffold that resembles the bone cavity and is able to cover the pore scaffold seen from the Scanning Electron Microscope (SEM). Scaffold pore size is smaller from range of 780.8 to 835.4 μm into 225.2 μm. MTT assay results showed that IBS paste is not toxic and experiencing proliferation (viability >100%) that are expected to trigger osteoblast cell growth when applied. Microbacterium test results showed that IBS paste is an antibacterial seen from inhibition zone diameter of Staphylococcus aureus and has a high strength-sensitive antibacterial. Thus, hydroxyapatite, gelatin and streptomycin composites had qualified as injectable bone substitute which applied in cases of spinal tuberculosis

EFFECT OF DEACETYLATION DEGREES VARIATION ON CHITOSAN NERVE CONDUIT FOR PERIPHERAL NERVE REGENERATION

Broken nerves could regenerate when exposed to simple injuries by using a nerve conduit that has appropriate physiological and mechanical ability to support the nerves regeneration around the fissure of trauma. One of the biopolymer for the conduit composition is chitosan because it is biocompatible, biodegradable, non-toxic, and has similarity structure as natural glycosaminoglycans. The aim of research is to synthesize chitosan with variation of Degrees of Deacetylation (DD) and characterize the DD influence on mechanical properties and biocompatibility. Research design is prospective observational. Chitosan was treated with a decrease in the DD method and an increase in the temperature with the strength of alkaline solution, which was NaOH solution with concentrations of 5%, 20%, 35%, and 50% within 2 hours with a heating temperature of 95°C. The results of each DD variation were 23.24, 46.55, 53.48, and 55.06. It was characterized by tensile test with tensile strength values of 0.25 - 1.18 MPa. The degradation test results tend to decrease with the increasing concentration of NaOH proving that samples are biodegradable. The surface morphology of samples shows a pore range of 61.52 μm - 220.3 μm. The best result is the chitosan sample with 35% NaOH because due to the tensile characteristic and a pore in accordance with normal standard. Tensile strength is around 0.41 MPa - 3.69 MPa and pore size around 40 μm – 250 μm to accelerate nerve regeneration. The results are expected to provide alternative solution of nerve conduit development for peripheral nerve defects

Hollowfiber Polyurethane-Collagen Coating Chitosan as Nerve Graft for Therapy of Peripheral Nerve Injury in Extreme Paralysis

Peripheral nerve injury with gaps between 5 and 30 mm can result in permanent paralysis because axons are cut. The distance between axons, which is more than 1-2 cm, needs graft in the form of nerve connecting pipe in order to repair the defects. A synthesis of hollowfiber polyurethane-collagen coated by chitosan was carried out to identify its potential as treatment accelerator for peripheral nerve injury. The result of Fourier Transform Infrared (FTIR) analysis showed multiple links between chitosan and glutaraldehyde, which can be seen in wavenumber shift from 1080-1100 cm-1 to 1002 cm-1. The degradation test result revealed that the sample displayed mass loss after it was soaked in simulated body fluid (SBF) for seven days. Polyurethane can be degraded in the body after 30 days. This converges with the nerve mechanism that regenerates at the rate of 1 mm/day or 1 inch/month. The result of tensile test indicated that modulus values of chitosan coating variation of 1%, 1.5%, and 2% were 4.75 MPa, 4.74 MPa, and 7.67 Mpa respectively. The outcome of scanning electron microscope (SEM) showed that hollow fiber has a diameter of 2.021-2.032 mm, which matches the diameter of peripheral nerves ranging from 1.5 to 3 mm and the membrane pore size of 31.33-39.65 μm. The result of MTT assay demonstrated that the percentage of viable fibroblast BHK-21 cells was exceeding 50%, which means that the sample does not have toxic properties. The result of this study is expected to provide theoretical basis for the utilization of polyurethane-collagen coating chitosan as nerve graft for theraphy of peripheral nerve injury. The utilization is possible due to the fact that the composite exhibits biocompatible, regenerative, and easily degradable characteristics. Moreover, it could become an alternative solution to answer the need of a more affordable and easier-to-produce nerve graft, so it can be mass-produced in Indonesia