The Influence of Sepsis on the Molecular Structure of Bones: A Fourier Transform Infrared Spectroscopy Study.

Fourier transform infrared spectroscopy was used to evaluate the molecular structure of bone tissues of patients who underwent revision of total hip and shoulder arthroplasty. The intensity increase of the spectral bands in the region of 3000-2850 cm-1 provided information about the increase of the lipophilic environment, which supported the formation of aggregates and amyloid protein formation. The appearance and the intensity increase of the "marker band" at 1744 cm-1 suggested protein peroxidation and inflammation progression. The shift of the amide I and amide II absorption bands from 1650 cm-1 and 1550 cm-1, respectively, to lower frequencies was related to changes of collagen conformation structure from α-helix to ß-sheet and random coil. The appearance and shifts of the new bands in the region 1200-900 cm-1 were related with the increasing of glycosylation upon inflammation. Important was also the disappearance of the hydroxyapatite vPO43- absorption bands at the spectral regions 1200-900 cm-1 and 550-650 cm-1 indicated the osteolysis development. Moreover, the formation of corrosive metallic implants confirmed the effect of oxidative stress on the development of periprosthetic joint infection.

Infrared and Raman Spectroscopic Studies of Molecular Disorders in Skin Cancer.

AIM: To investigate the molecular structural disorders of cancerous skin. MATERIALS AND METHODS: Human malignant melanoma and basal cell carcinoma biopsies were used for the investigation. Fourier transform infrared (FT-IR), Raman spectroscopy, and scanning electron microscopy were utilized. Spectral differences between healthy, basal cell carcinoma and melanoma tissues were recorded. RESULTS: The FT-IR bands of vasCH2, vsCH2 and Raman vsCH3 of cell membrane lipids were increased in intensity in melanoma due to an increased lipophilic environment. The FT-IR band at 1,744 cm-1 assigned to malondialdehyde can be used as a band diagnostic of cancer progression. The amide I bands at 1,654 cm-1 and 1,650 cm-1 for Raman and FT-IR, respectively were broader in spectra from melanoma, reflecting changes of protein secondary structure from α-helix to ß-sheet and random coil. The intensity of the FT-IR band at 1,046 cm-1 was increased in melanoma, suggesting glycosylation of the skin upon cancer development. Another band that might be considered as diagnostic was found at about 815 cm-1 in melanoma and was attributed to Z-DNA configuration. As far as we know, this is the first time that scanning electron microscopy revealed that metal components of titanium alloys from tooth implants were transferred to melanoma tissue taken from the back of one patient. CONCLUSION: Vibrational spectroscopy highlighted increased glycosylation in melanoma.

Oxidative stress in ageing and disease development studied by FT-IR spectroscopy.

FT-IR spectroscopy was used to investigate the effect of oxidative stress and to approach the mechanism on cancer bone demineralization, aortic valve mineralization and heterotopic ossification on disease development. The FT-IR spectra obtained from paediatric, adult bone and ex vivo irradiated adult healthy bone with a dose of 20Gy were compared with those of healthy bone. The increase of band intensity changes of vasCH2,vsCH2 in the region 3000-2850cm-1 depended on aging, the disease progression and the dose of irradiation. The bands at 3080cm-1 and 1744cm-1, which originate from olefinic terminal bond (v=CH) and ester carbonyl group (vROCO), respectively, indicate the influence of oxidative stress on lipid degradation and peroxidation, respectively. The new bands at about 1690cm-1 and 1516cm-1 denote the presence of ß-sheet conformation of the proteins due to the diseases, confirming the increasing amount of lipophilic environment and fibril formation. Comparison of the FT-IR spectra of calcified aortic valve and hip heterotopic ossification with that of normal bones showed that in the bone-like formation the peroxide anion free radicals play an important role in the disease.