title: New Evidences of Key Factors Involved in "Silent Stones" Etiopathogenesis and Trace Elements: Microscopic, Spectroscopic, and Biochemical Approach.
abstract: The knowledge of the key factors involved in etiopathogenesis of the gallstone disease requires chemical, structural, and elemental composition analysis. The application of different complementary analytical techniques, both microscopic and spectroscopic, are aimed to provide a more comprehensive determination of the gallbladder calculi ultrastructure and trace element identification. High sensitivity techniques such as electron microscopy (SEM), Fourier transform infrared (FTIR), electron paramagnetic resonance (EPR) spectroscopy, and X-ray diffraction (XRD) along with biochemical analysis are used in a new attempt to investigate various factors which play a regulatory role in the pathogenesis of gallstones. The microstructure of different types of gallbladder stones has specific characteristics which are related to the elemental composition. The binding of metal ions with bile salts and bilirubin plays important roles in gallstone formation as revealed by FTIR spectrum of calcium bilirubinate complex in pigment gallstones. The EPR results demonstrated the generation of bilirubin free radicals and variation of its electronic structure and conjugation system in the skeleton of bilirubin molecule during complex formation. EPR spectra of pigment gallstones demonstrate the coexistence of four paramagnetic centers including stable bilirubin free radical, Mn2+, Cu2+, and Fe3+ with distinct magnetic parameters and well-resolved hyperfine structure in the case of Mn2+ ions. The result confirms a macromolecular network structure with proteins and the formation of bilirubin-coordinated polymer. Bilirubin and bilirubinate free radical complexes may play an important role in pigment gallstone formation.
authors.affiliation: Faculty of Medicine and Pharmacy, University of Oradea, P-ta 1 Decembrie 10, 410087, Oradea, Romania. simona.cavalu@gmail.com.
authors.forename: Simona
authors.initials: S
authors.lastname: Cavalu
authors.affiliation: National Institute for R&D Isotopic and Molecular Technologies, 400293, Cluj-Napoca, Romania.
authors.forename: Adriana
authors.initials: A
authors.lastname: Popa
authors.affiliation: National Institute for R&D Isotopic and Molecular Technologies, 400293, Cluj-Napoca, Romania.
authors.forename: Ioan
authors.initials: I
authors.lastname: Bratu
authors.affiliation: National Institute for R&D Isotopic and Molecular Technologies, 400293, Cluj-Napoca, Romania.
authors.forename: Gheorghe
authors.initials: G
authors.lastname: Borodi
authors.affiliation: Faculty of Medicine and Pharmacy, University of Oradea, P-ta 1 Decembrie 10, 410087, Oradea, Romania.
authors.forename: Adrian
authors.initials: A
authors.lastname: Maghiar
mesh_terms: D001663:Bilirubin / Q000032:analysis / Q000737:chemistry; D002784:Cholesterol / Q000032:analysis; D003300:Copper / Q000032:analysis; D004578:Electron Spin Resonance Spectroscopy; D042882:Gallstones / Q000209:etiology* / Q000503:physiopathology*; D006801:Humans; D007477:Ions; D007501:Iron / Q000032:analysis; D008345:Manganese / Q000032:analysis; D008670:Metals / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D013053:Spectrophotometry; D017550:Spectroscopy, Fourier Transform Infrared; D014131:Trace Elements / Q000032:analysis*; D014961:X-Ray Diffraction
chemical_list: D007477:Ions; D008670:Metals; D014131:Trace Elements; D008345:Manganese; D003300:Copper; D002784:Cholesterol; D007501:Iron; D001663:Bilirubin
keywords: Etiopathogenesis; Gallstones; Microscopy; Spectroscopy; Trace elements