16 research outputs found
Thoracic aortopathy in Turner syndrome and the influence of bicuspid aortic valves and blood pressure: a CMR study
<p>Abstract</p> <p>Background</p> <p/> <p>To investigate aortic dimensions in women with Turner syndrome (TS) in relation to aortic valve morphology, blood pressure, karyotype, and clinical characteristics.</p> <p>Methods and results</p> <p>A cross sectional study of 102 women with TS (mean age 37.7; 18-62 years) examined by cardiovascular magnetic resonance (CMR- successful in 95), echocardiography, and 24-hour ambulatory blood pressure. Aortic diameters were measured by CMR at 8 positions along the thoracic aorta. Twenty-four healthy females were recruited as controls. In TS, aortic dilatation was present at one or more positions in 22 (23%). Aortic diameter in women with TS and bicuspid aortic valve was significantly larger than in TS with tricuspid valves in both the ascending (32.4 ± 6.7 vs. 26.0 ± 4.4 mm; p < 0.001) and descending (21.4 ± 3.5 vs. 18.8 ± 2.4 mm; p < 0.001) aorta. Aortic diameter correlated to age (R = 0.2 - 0.5; p < 0.01), blood pressure (R = 0.4; p < 0.05), a history of coarctation (R = 0.3; p = 0.01) and bicuspid aortic valve (R = 0.2-0.5; p < 0.05). Body surface area only correlated with descending aortic diameter (R = 0.23; p = 0.024).</p> <p>Conclusions</p> <p/> <p>Aortic dilatation was present in 23% of adult TS women, where aortic valve morphology, age and blood pressure were major determinants of the aortic diameter.</p
Single-path supercontinuum laser spectroscopy combining MIR-ATR and NIR transmission
The strong absorption of water in the mid-infrared (MIR) causes difficulties in performing combined near-infrared (NIR) and MIR spectroscopy on aqueous samples using a single instrument. Combining spectra from different instruments can result in unwanted spectral variations, which can influence the prediction models and mitigate the advantages of the combination approaches. In this work, absorption spectra were collected in the NIR (1300nm-2500nm) and MIR (2500nm-3800nm) region by combining a single high-brightness broadband supercontinuum (SC) laser spanning from ∼1-4.0 μm with attenuated total reflectance (ATR) and a transmission cuvette in a single-path configuration to provide a uniform spectral response across the NIR and MIR regions. The measured NIR- and MIR- spectra were assessed based on their ability to predict varying concentrations of ethanol, sucrose, and L-proline in aqueous solutions. The NIR-based partial least square regression (PLSR) model gave higher prediction accuracy for sucrose (R2 = 0.95) as compared to both ethanol and L-proline (R2 = 0.75 and R2 = 0.57 respectively). On the other hand, the MIR-based model enhances the prediction accuracy of ethanol (R2 = 1.00) and L-proline (R2 = 0.62) while demonstrating no significant change in prediction accuracy for sucrose (R2 = 0.96). The prediction models based on the combined NIR-MIR spectra performed similar but slightly worse than the MIR-only models for ethanol and L-proline (R2 = 0.97 and R2 = 0.54 respectively), while for sucrose, it was slightly improved (R2 = 0.99).</p