The innate, prominent vibrations were measured as described by Tarnowski et al. [22]. Crystallinity was determined using the method reported by Yerramshetty et al. [23] as the inverse of the width of the phosphate symmetric stretch band (PO 4 3− ν 1 at 959 cm−1) at half the maximum intensity value. A Nicolet Al.mega XR Dispersive Raman selleck screening library microscope

system equipped with the OMNIC Atlμs™ imaging software program (Thermo Fisher Scientific, MA, USA), which enable to map a small area less than 1 μm3 on the bony microsurface of the cortical bone on the video microscope stage control. A high brightness, low-intensity laser operating at 780 nm was used as the excitation source with a laser power of 35 mW. Each spectrum is the sum of ten 10-s measurements. The spectral resolution CH5424802 of the Almega XR under the conditions used was 3.85 cm−1. For each femur, one averaged Raman image was

acquired in the middle of the anterior cortical bone by the ten 10-s measurements. Statistical analysis All data values were expressed as the means ± standard deviation (SD). Unless otherwise mentioned, the group means for each parameter were determined for the 8-week midpoint experimental results and compared using a one-way analysis of variance (ANOVA), with the post hoc Tukey–Kramer test. Dunnett’s multiple comparisons test was used for 16-week treatment groups with the OVX group as a reference. The probability PJ34 HCl values of p < 0.05 were considered to be statistically significant for all the

comparisons. The Stat View software package (Stat View 5.0; Abacus Concepts, Berkeley, CA, USA) was used for all analyses. Results Body weight and length of femur The body weight, which was 33.6 ± 2.1 at the ovariectomy (−4 weeks), ranged from 37.4 ± 2.1 to 40.3 ± 3.0 g at 0 week in the sham and OVX groups. At 8 and 16 weeks, the range in all groups was between 40.9 ± 2.7 and 44.3 ± 4.3 g and 43.6 ± 7.5 and 49.4 ± 7.0 g, respectively. The length of the femur at the time they were killed ranged between 17.5 ± 0.6 and 17.8 ± 0.4 mm. Neither body weight nor the length of femur showed any significant difference in any of the treatment groups compared to the OVX or sham group (data not shown). While the body weight in OVX groups tended to be larger at 0 and 8 weeks, no significant effect was detected (data not shown). No intergroup difference was detected either (data not shown). Mechanical tests of femurs after the 16-week treatments As shown in the Fig. 1, the bending strength of the femoral diaphysis (top panels) and the compressive strength of the femoral distal metaphysis (bottom panels) were tested. In comparison to the OVX bone, a significant difference was detected in the sham bone as revealed by the elastic modulus as well as the ultimate stress values.