title: Study of normal colorectal tissue by FT-Raman spectroscopy.
abstract: FT-Raman spectroscopy was employed to study normal human colorectal tissues in vitro with the aim of evaluating the spectral differences of the complex colon mucous in order to establish a characteristic Raman spectrum. The samples were collected from 39 patients, providing 144 spectra for the statistical analysis. The results enable one to establish three well-defined spectroscopic groups of non-altered colorectal tissues that were consistently checked by statistical (clustering) and biological (histopathology) analyses: group 1 is represented by samples with the presence of epithelial layer, connective tissue papillae, and smooth muscle tissue; group 2 comprises tissues with epithelial layer and connective tissue papillae; group 3 presented mostly fatty and slack conjunctive tissue. The study reveals the existence of an intrinsic spectral variability for each patient that must be considered when sampling tissues fragments to build a spectral database. This is the first step for future studies and applications of Raman spectroscopy to optical biopsy and diagnosis of colorectal cancer.
authors.affiliation: Laboratory of Biomedical Vibrational Spectroscopy, Institute of Research and Development (IP and D), Universidade do Vale do Paraiba (UniVap), Av. Shishima Hifumi 2911, 12244-000 São José dos Campos, SP, Brazil.
authors.forename: P O
authors.initials: PO
authors.lastname: Andrade
authors.forename: R A
authors.initials: RA
authors.lastname: Bitar
authors.forename: K
authors.initials: K
authors.lastname: Yassoyama
authors.forename: H
authors.initials: H
authors.lastname: Martinho
authors.forename: A M E
authors.initials: AM
authors.lastname: Santo
authors.forename: P M
authors.initials: PM
authors.lastname: Bruno
authors.forename: A A
authors.initials: AA
authors.lastname: Martin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis* / Q000737:chemistry*; D003106:Colon / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012007:Rectum / Q000737:chemistry*; D012016:Reference Values; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D013059:Spectrum Analysis, Raman / Q000379:methods*
chemical_list: D015415:Biomarkers