Table 1.
Diffusion measurements of artificially degraded cartilage1
| Method | D/MD1 (native) |
D/MD1 (treated) |
Diff. (%) |
FA (native) |
FA (treated) |
Diff. (%) |
Treatment [Doses] |
Time | N | GAG loss | Ref. |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Spect | 0.72–1.42 | 0.83–1.56 | 10–15 | – | – | – | Trypsin | – | – | – | (29) |
| [25 mg/ml] | |||||||||||
| Spect | 1.35 | 1.62 | 20 | – | – | – | Trypsin | 5–180 min | – | 0–13 µmol | (29) |
| [25 mg/ml] | |||||||||||
| DWI | 1.27 | 1.49 | 17 | – | – | – | Trypsin | – | 1 | – | (29) |
| [25 mg/ml] | |||||||||||
| Spect | – | – | 25 | – | – | – | Trypsin | 5–180 min | 34 | 60–80% | (30) |
| [25 mg/ml] | |||||||||||
| Spect | – | – | 30 | – | – | – | Hyaluronidase | 2–8 h | 10 | 60–87% | (30) |
| [100 units/ml] | |||||||||||
| Spect | – | – | <5 | – | – | – | Retinoic acid | 4 days | 16 | 10–70% | (30) |
| [0.0025–10 µg/ml] | |||||||||||
| Spect | – | – | 15 | – | – | – | Collagenase | 1 day | 10 | 5–50% | (30) |
| [0–225 units/ml] | |||||||||||
| DWI | 1.05±0.02 | 1.12±0.07 | 7 | – | – | – | EDTA | 1 day | 3 | 2.5±0.8% | (103) |
| (1D) | [204 mg/ml] | ||||||||||
| DWI | 1.08±0.08 | 1.18±0.08 | 9 | – | – | – | Gu-HCL | 1 day | 9 | 69±16% | (103) |
| (1D) | [382 mg/ml] | ||||||||||
| DWI | 1.07±0.02 | 1.08±0.02 | 1 | – | – | – | NaCl | 1 day | 5 | 0.7±0.4% | (103) |
| (1D) | [8.77 mg/ml] | ||||||||||
| Spect | 1.35±0.22 | 2.00±0.22 | 41 | – | – | – | Trypsin | 15–205 min | 2 | – | (99) |
| [25 mg/l] | |||||||||||
| DWI | 1.40±0.19 | 1.80±0.19 | 29 | – | – | – | Trypsin | 4 h | 1 | – | (99) |
| [25 mg/l] | |||||||||||
| DWI | 1.33±0.22 | 1.84±0.14 | 38 | – | – | – | Trypsin | 4 h | 2 | – | (99) |
| [25 mg/l] | |||||||||||
| DWI | 0.93±0.10 | 1.13±0.06 | 22 | – | – | – | Trypsin | 18 h | 120 | 62.8% | (100) |
| [Trypsin] | [1 mg/ml] | [Trypsin] | [Trypsin] | ||||||||
| 1.04±0.07 | 12 | Collagenase | 20 h | 13.2% | |||||||
| [collagen.] | [30 units/ml] | [collagen.] | [collagen] | ||||||||
| DWI | 0.93±0.10 | 0.96±0.10 | 3 | – | – | – | Trypsin | 6 h | 120 | – | (102) |
| [Trypsin] | [1 mg/ml] | [Trypsin] | |||||||||
| 0.97±0.09 | 4 | Collagenase | 18 h | ||||||||
| [collagen.] | [30 units/ml] | [collagen.] | |||||||||
| DWI | 1.01±0.09 | 1.25±0.08 | 24 | Trypsin | 24 h | 36 | 77% | (101) | |||
| [1 mg/ml] | [Trypsin] | ||||||||||
| DTI3 | 1.80±0.18 [AS] | 1.9 [AS] | 10–15 | 0.10 [AS] | 0.05 [AS] | – | Trypsin | 14 h | 15 | ~100%2 | (21) |
| 0.79±0.15 [BCI] | 1.0 [BCI] | 0.50 [BCI] | 0.20 [BCI] | [100 mg/ml] | |||||||
| DTI4 | 1.54±0.14 | 1.69±0.09 | 10 | 0.10±0.01 | 0.09±0.02 | −10 | Trypsin | 24–48 h | 6 | 68% | (22) |
| 1.43±0.14 | 1.65±0.14 | 15 | 0.10±0.01 | 0.10±0.01 | 0 | [25 mg/ml] | 75% | ||||
| 1.23±0.14 | 1.39±0.17 | 13 | 0.15±0.02 | 0.15±0.02 | 0 | 76% | |||||
| DTI5 | 1.34±0.02 | 1.44±0.07 | 7 | 0.10±0.01 | 0.11±0.01 | +10 | Trypsin | 24 h | 3 | 96% | (22) |
| 1.32±0.03 | 1.47±0.07 | 11 | 0.11±0.02 | 0.12±0.02 | +9 | [25 mg/ml] | 99% | ||||
| 1.21±0.03 | 1.43±0.17 | 18 | 0.16±0.02 | 0.19±0.03 | +19 | Collagenase | 9 days | 98% | |||
| [60 nM] | |||||||||||
| DTI | – | 0.25±0.03 | 20.6 | – | 0.03 | 0 | Trypsin | 6–96 h | 12 | −40 – −1205 | (24) |
| [96h trypsin] | [96 h trypsin] | [0.1 mg/ml] | |||||||||
| 0.07±0.04 | 0.03 | ||||||||||
| [Controls] | [Controls] |
The diffusion coefficient (D) for spectroscopy (Spect.) and diffusion-weighted imaging (DWI). MD was used for diffusion-tensor imaging (DTI) acquisitions (in units of 10−3 mm2/s). 1D indicates that imaging was performed in one dimension. Diff. = Relative difference. Bold face indicates significant (P<0.05) difference if provided in the reference. N=number of samples. Ref. = Reference
PG loss measured as the change in absorbance at 475 nm in safranin-O slides. After treatment absorbance changed 2 to almost 0, no direct quantification was reported.
AS=Articular surface; BCI=Bone cartilage interface.
Analysis performed by dividing the cartilage into three layers. Data presented for the 1/3 superficial, 1/3 middle and 1/3 deep layers.
Semiquantitative assessment of the PG loss based on the change in the staining of the safranin-O slides. Reproducibility of the method ±9 units.