The aim of this thesis was develop a computational modeling and in vitro testing of the mechanical and biological properties of collateral knee ligament fibroblasts treated with therapeutic ultrasound. Pulsed ultrasound at 1.0 MHz with two different intensities 1.0 W/cm2 (Group A) and 2.0 W/cm2 (Group B) was applied every 24 hours for five days to ligament fibroblasts monolayer cultured. Group C was untreated control group. The author measured cell elastic modulus using an Atomic Force Microscopy (AFM) testing, harmonics with Finite Element Method, viability by flow cytometry analysis, proliferation via colorimetric assay (MTS), synthesis of type I, type III collagen and fibronectin using the Enzyme Linked Immunosorbent Assay (ELISA) assay, and cell migration through wound
scratch assay. The results showed a decreased cell elastic modulus (22% and 31%, p<0.05), harmonics (20% and 20%) with non-resonance effect, and viability (1% and 10%) due low and high intensity, respectively. Cell proliferation was raised 10% and diminished 13% (p<0.05). Type I collagen was increased 100% for high intensity, and no collagen synthesis was detected for low intensity and control group. Fibronectin production was increased 79% and 61%. Cell migration was increased 4% and decreased 11% (p<0.05). These findings suggested that low and high doses of ultrasound may improve either stage
of healing, early (regenerative) or late phase (remodeling) by decreasing the elastic modulus due cytoskeleton rearrangement to allow cell functionality and motility. This work argued that pulsed therapeutic ultrasound might be used to stimulate cells to improve the ligament healing process.
| Date of Award | 2019 |
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| Original language | Spanish (Colombia) |
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| Supervisor | Diego Garzón alvarado (Supervisor) & Alba Avila (Supervisor) |
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- ligament fibroblasts
- pulsed ultrasound
- elastic modulus
- harmonics
- viability
- proliferation
- extracellular matrix proteins
- migration