Photon Factory Activity Report 2014 #32 (2015) B

BL-11B/2012G626

Further Analysis of the Relation between Oxidative Damage and Ca Accumulation
Examined by X-ray Contact Spectromicroscopy with Electronic Zooming Tube
Atsushi Ito1, *, Takafumi Inoue2, Tomomitsu Kawai2, Fumihisa Ouchi1, Yuto Inoue1,Kunio Shinohara1
1
School of Engineering, Tokai Univ., Hiratsuka, Kanagawa 259-1292, Japan2
Kao Corporation, Odawara, Kanagawa 250-0002, Japan
1 Introduction
We have been comparing the distributions between Ca
content and oxidative damage in human hair in order todiscriminate Ca accumulation by external stimuli fromthe one supplied from blood flow around hair matrix cells
at the hair root [1]. The information about the distributionof the latter Ca may be worth for applications to medical
diagnosis such as forecasting human breast cancer [2].
Recently we found that increase in Ca caused by bleachtreating oxidative damage mainly distributes in outerregion called cuticle and cortex, while Ca distribution inmedulla, a central part of hair, seems to be independent ofoxidative damage [3, 4], suggesting that Ca in medulla
may be useful for the medical purpose. In the present
study, we extended this observation to the samples ofage-related positions of a hair from its root.
2 Materials and Methods
For the mapping of cysitne, cysteic acid and Ca X-ray
contact microscopy with an electronic zooming tube witha resolution of about 0.5 m was employed at the S-K
edge and Ca-K edge at BL-11B. Since highly sensitive Ca
mapping with X-ray fluorescence analysis has not
unfortunately been available any more at BL-4A, thisstudy was also aimed to study the applicability of theelectronic zooming tube system having lower sensitivity
than that of X-ray fluorescence analysis.
Human hair specimens with medulla were selectedusing an IR scope. For the bleach treatment in thelaboratory, hair specimens were soaked twice in asolution containing 1.2 % ammonia and 3.5 % hydrogen
peroxide for 30 min. Ca soaking was performed with 10mM CaCl2 for 2 days with a daily change of the solution.
These treatments were done for different specimens fromthe same lot. At the positions of around 1 cm and 10 cm
from the root side, they were cut at the thickness of about
20 m, and then placed on a SiN membrane with 100 nmthickness. The opposite side of the membrane was coatedwith Au as a photocathode of the zooming tube.
3 Results and Discussion
Fig. 1 shows X-ray images of cystine, cysteic acid andCa in human hair specimens at the position of 10 cm fromthe root. Bleach treatment with subsequent Ca soaking
increased Ca content particularly in the cuticle and cortex
regions (panel c) by comparing image of untreatedspecimen (panel a), although the Ca images did not havea good contrast and sensitivity compared with X-ray
fluorescence images. In the untreated hair little Ca wasdetected in cuticle and cortex regions, while medulla had
detectable amount of Ca. These results were also obtained
for specimens of 1cm from the root. However the resultscannot exclude the possibility that Ca in medulla also
increased with bleach treatment in addition to the intrinsic
Ca. Determination of chemical form of Ca in medulla andother areas is definitely useful. Based on ourmeasurement of XANES of various Ca compounds
including CaCl2 [1], comparison of XANES profiles inhair with that of CaCl2 is planned.
CystineCysteic acidCa(a)(b)(c)Fig. 1: Cystine, cysteic acid and Ca distributions inhuman hair with medulla. (a) control, (b) bleaching,(c) soaking in CaCl2 solution after bleaching.
References[1] A. Ito et al., Adv. X-ray Chem. Anal., Japan, 43, 161(2012). (in Japanese)[2] J. Chikawa et al., J. X-ray Sci. Tech., 15, 109 (2007).
[3] A. Ito et al., PF Activity Report 2013, 31, 73 (2014).
[4] A. Ito et al., Proceedings of the 12th International
Conference on X-Ray Microscopy (submitted)* aeito@keyaki.cc.u-tokai.ac.jp