Journal of IiME Volume 1 Issue 2 www.investinme.org Visible and near-infrared (Vis-NIR) spectroscopy: Introduction and Perspectives for Diagnosis of CFS (continued) Fig. 3. PCA of Vis-NIR spectra of serum samples for CFS diagnosis (A-B) Vis-NIR spectra of serum samples from healthy donors (Blue) and CFS patients (Red) were subjected to PCA and the results plotted as PC1 versus PC2 to establish a PCA model (A). Loadings show the importance of each wavelength for the PCs indicated by peaks (B). (C) Masked samples, which were not used for development of the model, were subjected to PCA and the results plotted as PC1 versus PC2. Modified from Fig. 1 in Sakudo et al. [86] with permission from Elsevier. spectra of 148 individuals including 77 CFS patients and 71 healthy donors, not a sufficient number for practical use in the clinic. The influences of sex and race, etc. on the results of this diagnostic method remain unclear. To obtain more Vis-NIR spectra, samples for the calibration set should be obtained in a similar way to those that will be analyzed for diagnosis. Furthermore, uniformity of the solvent among samples is very important. For example, in blood samples, identical methods of preparation of serum are necessary. Stable humidity and temperature should be maintained during the scanning event, because humidity and temperature may affect water absorption in the NIR region. In this study, we used serum samples for Vis-NIR spectroscopy. Therefore, the method is invasive but nondestructive. Vis-NIR spectroscopy can also be applied to non-invasive analyse and we are now approaching the Invest in ME Charity Nr 1114035 non- invasive diagnosis of CFS (Fig. 5).Hopefully, after these issues are addressed, this diagnostic method might be adopted in the clinic (Fig 6). The next step in terms of research into the disease, as opposed to diagnosis, is to use this approach together with other evidence to try and identify specific biochemical markers common to CFS. This is the best way to understand the cause of CFS. Our experimental system coupling Vis-NIR spectroscopy with chemometrics may also contribute to this issue. Finally, we would like to emphasize that international collaboration is important in the development of this method, because CFS is heterogeneous and diagnostic criteria differ slightly among countries. Differences and similarities between CFS and CFS-like diseases such as ME, PVFS, CFIDS, and ‘Yuppie flu’ would also be made clear by this method. (continued on page 14) Page 13/72

14 Publizr Home

You need flash player to view this online publication