Figure 9. Polydispersity and viscosity data of the 15 mm scaffold in vivo and in vitro series (n = 2 for all data points). The weight loss of the three scaffold sizes was noticed to begin around the week 28. At week 48, there was a 10% mass loss observed for all the scaffold sizes. When the 15 mm sample weight loss data are plotted against selleck chem the GPC results (Fig. 10), we can observe that the weight loss starts when the molar mass is less than 20 kDa, and it increases more rapidly when the molecular weight is less than 10 kDa. Figure 10. Weight loss data (n = 3) plotted against the Mw (n = 2) during the 15 mm scaffold in vitro incubation. In vivo results of the cylindrical scaffolds We can see from the compression test curves (Fig. 7A�CD) that the scaffold loses its stiffness in vivo before the week-2 test point.
After 12 weeks, we can see a rise in stiffness, and it is further increased until week 48. The degradation rate of the PLA96 fibers in scaffold format in vivo is statistically significantly different after 6 weeks when compared with the degradation rate in vitro. Implanted scaffolds after of 52 weeks had Mw 18 kDa and Mn 12 kDa, whereas it was only 8 kDa after 48 weeks in vitro. However, both of the degradation profiles follow the same trend for the first 4 weeks, after which we can see a delay in the in vivo degradation that eventually leads to a slower degradation compared with the in vitro degradation. The viscosity is also statistically significantly different compared with in vitro samples. There is a clear lag in the viscosity drop in vivo, and in the case of PD, we cannot notice any statistically significant changes.
The 52-week specimens were visually examined (Fig. 11), and we can see that the scaffold is still present, visible, maintaining its form and tightly packed in dense connective tissue. Figure 11. The scaffold after 52 weeks of implantation. Discussion The tensile strength of the yarn in the knit is lower than that of the yarn tested prior the knitting. This is due to damage done to the fibers during the knitting as well as due to the non-unidirectional forces inflicted on the yarn due to the loops. For our specimens, the behavior of the 0-week knits was as expected. Similar break forces for 4-ply knits with equal knitting properties were reported earlier by Kellom?ki,9 although the strain property of our knit was ~17% higher.
Brefeldin_A The higher strain values are influenced by the knit density, which was lower in our study. Increasing the number of needles in the tubular weft knit statistically significantly increased the measured tensile load. Increasing the number of single filaments in fibers in the tubular weft knit has a statistically significant effect on tensile load of certain structures; the only statistically insignificant difference was indicated between 8F-9Nb and 4F-9Nb knits. Higher numbers of filaments in fibers also affect the knitting properties.