05, Wilcoxon rank test), left and right diffusion parameters values of each bundle were pooled for subsequent analyses. From a structural point of view, each bundle had specific diffusion tensor characteristics (Fig. 5; Table 1). CST was the most organized structure exhibiting significantly lower ADC values compared to OR, genu, body, and splenium of CC (ANOVA, P < 0.05 corrected for multiple comparisons) (Fig. Inhibitors,research,lifescience,medical 5). CST also showed higher FA values

compared to OR, genu, and body of CC (ANOVA, P < 0.05 corrected for multiple comparisons) (Fig. 5). In contrast, OR appeared as the less-organized structure with significant higher ADC relative to CST, body, and genu of CC, and significant lower FA compared to all the others tracts (ANOVA, P < 0.05 corrected for multiple comparisons). Table 1 Mean values (± standard deviation) of apparent diffusion coefficient Inhibitors,research,lifescience,medical (ADC), fractional anisotropy (FA), longitudinal diffusivity (λ//), and transverse diffusivity (λ) Figure 5 Comparison of diffusion tensor properties observed in the different tracts. Boxplots of ADC (mm2/s),

FA, λ// (mm2/s), and λ (mm2/s) values at the body of corpus callosum (CCb), the genu of corpus callosum (CCg), the splenium of … Variation of WM tract diffusion characteristics according to gestational Inhibitors,research,lifescience,medical age According to the poor linear fitting of diffusion parameters with age, the Sorafenib solubility dmso polynomial function of degree 3 was chosen to model the variation of parameters during gestation. We defined the transition periods between the different stages of maturation numerically from the intersections of the λ// and λ polynomial fitting functions according to age. In order to normalize variations and dynamics of the different Inhibitors,research,lifescience,medical parameters, values were rescaled according to the Z-score formula using the mean values and standard deviations of the whole population for each parameter. Each normalized parameter was plotted against age

for each bundle and the distribution was fitted using a 3 degree polynomial Inhibitors,research,lifescience,medical function. Models were valid (R > 0.5 and P < 0.05) for all diffusion parameters L-NAME HCl of each bundle except for diffusion parameters of the genu of CC (P = 0.10–0.9), the FA of the body of CC (P = 0.16), and the λ// of the splenium (P = 0.11). During the 23–38 GW period, differences in the relative variations of longitudinal (λ//) and radial diffusivity (λ) curves identified three distinct phases of water molecule restriction (Fig. 6). The transition between two phases was determined as the time point when normalized λ// and λ curves versus gestational age were crossing. The precise time point was determined numerically by equalizing the two equations of the polynomial fitting curves. Figure 6 Variation of diffusion parameters during gestation according to the WM structure.