To detect the bone quality loss in osteoporosis, we performed Raman spectroscopic analysis of sciatic nerve resection (NX) mice. Eight months after surgery, lower limbs were collected from the mice and fixed with 70% ethanol. Raman spectra of anterior cortical surface of the proximal tibia at 5 points in each bone were measured by RENISHAW inVia Raman Microscope. Excitation wave length was 785 nm. We also performed DXA and micro CT measurement to confirm the bone mineral density and bone microstructure in the osteoporotic model induced by sciatic nerve resection. In the result of Raman spectroscopy, we detected changes of Raman peak intensity ratio in carbonate/phosphate, mineral/combined proline and hydroxyproline and mineral/phenylalanine. In addition, in the result of micro CT, we found significant changes in VOX BV/TV, Trabecular number, thickness, cancellous bone mineral density, cortical thickness and cortical bone mineral density. The results suggest that not only the bone mineral density but also bone quality reduced in the NX mice. We conclude that Raman spectroscopy is a useful for bone quality assessment as a complementary technique for conventional diagnostics.
To evaluate the bone quality in the osteoporosis, we generated sciatic nerve resection (NX) mice as an osteoporosis model and analyzed by Raman spectroscopy. Raman spectra were measured in anterior cortical surface of the proximal tibia at 5 points in each bone. After that, the samples were fixed with 70% ethanol. We then performed DXA and μCT measurement. Raman peak intensity ratios were significantly different between NX and Control. Those changes in the Raman peak intensity ratios may reflect loss of bone quality in the osteoporosis model. Raman spectroscopy is a promising technique for measuring the bone quality and bone strength.
Automatic determination of the cell shapes of large numbers of melanocytes based on optical images of human skin
models have been largely unsuccessful (the complexities introduced by dendrites and the melanin pigmentation over the
keratinocytes to give unclear outlines). Here, we present an image enhancement procedure for enhancing the contrast of
images with removing the non-uniformity of background. The brightness is normalized also for the non-uniform
population density of melanocytes.
Using the measured Raman spectra of triolein and cholesteryl linolenate, the contradiction caused in determining the
sequential orders in the two-dimensional correlation spectroscopy was exemplified, in which time-profiles of four
marker bands A, B, C, and D were modeled so that A→B→C→D. Here ‘A→B’ is such notation that we read as ‘A is
occurred before B’ or ‘A earlier than B’. The two-dimensional correlation method gave the result B→C→D→A which
was contradictive to the initial setting. We confirmed that the increments of distance between the peak positions of the
Gaussian type time-profiles ƒ and g, through a threshold, gave the unexpected switch in the sequential order. On the
complex plane based on the synchronous and asynchronous axes, the vector g is identical to the synchronous axis in
direction; the vector ƒ is crossed through the asynchronous axis corresponding to the increments of distance between the
peak positions of ƒ and g. By the conventional rule of the correlation method, the vector ƒ just crossing the asynchronous
axis is not allowed to be in the second quadrant, but the vector ƒ is transformed to the fourth quadrant with 180 degrees
shifted. In the situation, the vector ƒ is located in the later position for the standard vector g, that is, ƒ is occurred ‘after’ g.
Based on the revealed mechanism for the contradiction, the time series correlation analysis may be extended in a more
versatile manner to allow bio-Raman correlation analysis on diverse dynamics of bio-molecules in living cells.
One of suspect environmental endocrine disruptors that affect mouse male reproduction by altering the morphology of Sertoli cells and spermatogenic cells is phthalate. The effects of mono(2-ethylhexyl)phthalate (MEHP), one of metabolites of di(2-ethylhexyl)phthalate , on immature mouse testes in vivo were examined. We have recently shown
that MEHP induced Sertoli cells necrosis and spermatogenic cells apoptosis in mice by TUNEL method, F-actin staining,
and ultrastructural study, but there is no data for biochemical changing of testes due to those methods could not explore.
To verify in detail of it, we conducted Raman spectroscopy study with 785 nm wavelength laser line, 50mW of laser power and 3 minutes of exposure time to analysis the MEHP-treated testicular tissue, which has been fixatived by 4% paraformaldehyde (PFA). Five weeks old (5 w.o) male mice were used in this experiment. As the results, the alterations were observed by Raman spectroscopy that there are significantly differences of DNA, actin filament, type IV collagen and amide I between control group (0 μM MEHP) and treatment group (100 μM MEHP). These results significantly support histology staining observation (such as the apoptotic spermatogenic cells which is associated with DNA fragmentation and F-actin disruption) and ultrastructural observation (such as mitochondria rupture and disintegration of nucleus membrane). Raman spectroscopy can be used for 4% PFA-fixatived tissue observation. However, we recommend that Raman spectroscopy may be able to be expanded as an armamentarium not just for the clarification of histology staining and ultrastructural study, but furthermore, it may be as a non-invasion assessment for screening animal tissue toxicity of chemical in future.