The pathophysiological mechanism of increased fractures in young adults with type 1 diabetes mellitus (T1DM) is unclear. We conducted a case-control study of trabecular bone microarchitecture and vertebral marrow adiposity in young women with T1DM. Thirty women with T1DM with a median age (range) age of 22.0 years (16.9, 36.1) attending one outpatient clinic with a median age at diagnosis of 9.7 years (0.46, 14.8) were compared with 28 age-matched healthy women who acted as controls. Measurements included MRI-based assessment of proximal tibial bone volume/total volume (appBV/TV), trabecular separation (appTb.Sp), vertebral bone marrow adiposity (BMA), and abdominal adipose tissue and biochemical markers of GH/IGF-1 axis (IGF-1, IGFBP3, ALS) and bone turnover. Median appBV/TV in cases and controls was 0.3 (0.22, 0.37) and 0.33 (0.26, 0.4), respectively (p ¼ 0.018) and median appTb.Sp in T1DM was 2.59 (2.24, 3.38) and 2.32 (2.03, 2.97), respectively (p ¼ 0.012). The median appBV/TV was 0.28 (0.22, 0.33) in those cases with retinopathy (n ¼ 15) compared with 0.33 (0.25, 0.37) in those without retinopathy (p ¼ 0.02). Although median visceral adipose tissue in cases was higher than in controls at 5733 mm 3 (2030,11,144) and 3460 mm 3 (1808, 6832), respectively (p ¼ 0.012), there was no difference in median BMA, which was 31.1% (9.9, 59.9) and 26.3% (8.5, 49.8) in cases and controls, respectively (p ¼ 0.2). Serum IGF-1 and ALS were also lower in cases, and the latter showed an inverse association to appTbSp (r ¼ -0.30, p ¼ 0.04). Detailed MRI studies in young women with childhood-onset T1DM have shown clear deficits in trabecular microarchitecture of the tibia. Underlying pathophysiological mechanisms may include a microvasculopathy.

The surface-extended X-ray absorption fine structure (SEXAFS) spectrum of an electrochemically deposited adlayer of copper on a gold(lll) electrode immersed in solution and under potential control was obtained by employing fluorescence detection and grazing incidence geometry. The X-rays were polarized parallel to the plane of the gold surface. Two peaks were observed in the radial distribution function, indicating two different near neighbors for copper. The near neighbors were determined to be gold at 2.58 ± 0.03 Á and copper at 2.92 ± 0.03 A. The copper-copper distance is identical with the gold-gold lattice spacing, showing that at full coverage the copper adlayer forms a 1X1 commensurate layer on the gold(lll) substrate. The intensity of the gold-copper scattering relative to the copper-copper scattering suggests the copper atoms sit in 3-fold hollow sites.

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