Research ArticleExperimental Studies

An FT-IR Spectral Analysis of the Effects of γ-Radiation on Normal and Cancerous Cartilage

MARIA KYRIAKIDOU, ANDREAS F. MAVROGENIS, STYLIANOS KYRIAZIS, ATHINA MARKOUIZOU, THEOPHILE THEOPHANIDES and JANE ANASTASSOPOULOU
In Vivo September 2016, 30 (5) 599-604;

Abstract

In the present study we used non-distractive physicochemical methods to investigate the effect of γ-radiation on human articular cartilage. Comparison between the FT-IR (Fourier transform infrared) spectra before and after irradiation of the cartilage with different doses of radiation showed considerable changes in the spectra. It was found that for doses up to 2 Gy the collagen helices changed their structure from α-helix to random coil. By increasing the radiation dose it was found that the proteins' structure changed further to amyloid-like protein formation and to fragments of glycosaminoglycan chains, which were indicated in the IR spectra. Furthermore, comparison between the spectra of normal and irradiated cartilage, cancerous cartilage and cartilage from patients who received radiotherapy showed similarities in the spectra together with the formation of an aldehyde absorption band at 1740 cm−1 suggesting that in all cases of cartilage examined,oxidative stress played major role in the damage progression of cartilage.

Radiation therapy is currently applied for local effects to patients with bone and soft tissue cancers, aiming to facilitate the surgical procedure and improve patient survival. However, during treatment along with tumor cells,non-cancerous (normal) cells are also irradiated. Although radiation therapy remains an essential treatment of cancer, it is often associated to unwanted complications, such as bone and cartilage damage (1-3). There are many studies, that have demonstrated bone and cartilage damage following the exposure (4, 5), but they do not define the damaged structure of the tissues at a molecular level.

Dose-escalation studies to determine the maximum-tolerated dose of radiation at any given site and to evaluate models for hypo-fractionated radiation therapy within the context of predicting radiation-associated complications are difficult to carry out. This is because the radiation dose is usually limited by late normal tissue effects and great care must be taken not to cause unacceptable levels of late complications (6-7). Moreover, even fewer studies exist today, that have compared the effect of radiation with other diseases of human tissue (2).

Thus, we performed this study using FT-IR spectroscopy as a non-distractive method in order to examine the system of cartilage to evaluate the effect of radiation to human cartilage at the molecular level and to compare this effect with non-irradiated normal, arthritic and cancerous cartilage from patients with and without radiotherapy. Our primary hypothesis was that radiation has a significant and quantifiable effect in tissues and the secondary hypothesis was that this effect is similar to the effect produced in tissues by diseases such as arthritis and cancer.

Materials and Methods

Human articular cartilage specimens were harvested from totally 42 patients who underwent orthopaedic surgery for various reasons. From the study were excluded patients with other metabolic diseases. The cancerous samples were not irradiated. Next, each cartilage specimen was cut into 5-μm thick sections and as many pieces as there were corresponding radiation doses. The cancerous specimens had a size of 3 mm and they were analyzed using ATR-FT-IR technique in order to be used again for further studies (SEM and XRD).

Infrared spectroscopy (IR). The FT-IR spectra were carried out on the Mirage LURE (Centre Universitaire, Paris-Sud, Orsay, France), port SA5-Super ACO SOLEIL beamline using a spectrophotometer Thermo Nicolet Magma 550 (USA) coupled to an infrared microscope (Nicplan-Thermo Nicolet), equipped with a liquid nitrogen cooled mercury cadmium telluride (MCT) detector and with an ATR-FT-IR Nicolet 6700 thermoscientific spectrometer (Thermo Electron Corporation, Madison, WI, USA). Each spectrum was acquired after 64 and 120 co-added interferograms at a spectral resolution of 4 cm−1. Data analysis was performed using Omnic software, (Version 7.2a, Thermo-Nicolet) as was described alsewhere (2, 8-10). Infrared spectroscopy is a powerful method, when applied to tissue analysis, simple, fast and not costly to evaluate and characterize complex biological systems at a molecular level. Any component of the tissue influence the spectrum, which is a superimposition of any component single spectral and simultaniously are analyzed. The advantage of the method is that requires a small amount of sample without any previous preparation, such as demineralization, paraffin incubation and coloring as in histopathology (2, 8-10).

Scanning electron microscopy (SEM). The scanning electron microscope (SEM) and the microanalyzer probe, which was used to illustrate the architecture and morphology of the bone surface before and after irradiation, was of Philips SFEG XL 40 series (Eindhoven, The Netherlands). The samples were coated with Au.

Gamma rays 60Co source. The cartilages were irradiated using γ-60Co course(Gammachamber 4000A) of Atomic Energy of India, and the dose was calculated by Fricke dosimeter and the samples were exposed to 2 Gy up to 60 Gy

Results

The FT-IR spectra of the irradiated and non-irradiated cartilage samples are shown in (Figure 1).

In the spectral region of 3500-3000 cm−1 appear the bands due to stretching vibrations of vNH and vOH groups of collagen and glycosaminoglycans in cartilage, as well as the stretching vibration bands of water molecules (9, 10). The band at 3484 cm−1 is assigned to the stretching vibration of vOH groups of water molecules, and to the polysaccharides hyaluronic acid, which is a key component of cartilage. The intense band at 3292 cm−1 is assigned to stretching vibration of vNH groups of proteins and shows that the protein formulation is in the form Amide A11. Deconvolution analysis showed that this band consists of five absorption bands (spectra not included here), which correspond to stretching vibrations of vNH groups of proteins and vOH of glycosaminoglycans, which interact between them and are being linked with different hydrogen bonds.

The band which appears at about 3061 cm−1 indicates that some of the proteins have the configuration of Amide B. In the case of Amide B the b-sheet protein structure predominates (11). This means that the effect of the NH group of the peptide bond is superior to C=O, unlike in Amide A, where the effect of C=O is superior, i.e., it plays a more important role in structure making. The coexistence of both conformations of proteins in A and B forms illustrates the prevalence of different hydrogen bonds that hold the protein strands (9, 11). As known, hydrogen bonding is important in stabilizing the protein helix and any change implies that the physiological environment changes its normal configuration. We have found that these changes are very important and constitute a basic criterion in order to observe the disease and its progression (12-15).

By comparing the two spectra before and after radiation it is shown that after irradiation the bands decrease in intensity and become broad, leading to breaking of the hydrogen bonds, which exist in healthy cartilage and that the new products (fragments) do not interact via hydrogen bonding as before or the hydrogen bonding becomes much weaker. This is shown from the shift of OH and NH to absorptions at higher frequencies near 3600 cm−1.

The bands in the spectral region between 3000 cm−1 to 2870 cm−1 are assigned to the symmetric and antisymmetric stretching vibrations of methyl (vasCH3, vsCH3) and to methylene (vasCH2) groups of lipids, proteins and glycosides (9, 10). A considerable increasing of intensity of these bands was observed after irradiation showing that the environment of the membranes has now changed and that the surrounding medium became more lipophilic (12-14) (Figure 1).

The spectral region 1800-700 cm−1 contains information about the secondary structure of proteins. The high intensity band at 1743 cm−1, that appeared after irradiation, is assigned to the aldehyde group (-CHO), as a result of lipid peroxidation (12-14). The high-intensity band at 1650 cm−1 is assigned to the bending vibration δNH of the Amide I of the peptide bond (-NHCO-) of proteins (8-17). The Amide I band is a combination band of the stretching vibration vC-N group and the in-plane bending vibration δN-H of the peptide bond and is very sensitive to changes in both the environment and the conformations of the protein chains depending on the form of collagen and on the state of the disease (14-17). The intensity of this band decreases and shifts to lower frequencies upon irradiation. This shift is dependent on the irradiation dose showing that the secondary structure of proteins changed from α-helix to random coil. By increasing the dose over 6 Gy new bands were observed at about 1690 cm−1, indicating that some of the proteins changed their structure into amyloid-like structure (14, 15), in agreement with the increased intensities of the aliphatic bands in the region between 3000-2850 cm−1. The next intense band at about 1540 cm−1 is assigned to the vibration of the group Amide II of the proteins and the band is attributed to the β-turn of the protein and it suggests that the collagen helix has α-helix configuration. This band was also decreased and shifted to lower frequencies upon irradiation, indicating a damage of the native structure.

At the last spectral region 1250-900 cm−1 absorb the vibrational modes of the groups –C-O-C-, where an oxygen atom linking two carbon atoms of the sugar moiety of glycosaminoglycan together with the exocyclic C-O-C inter-molecule group. Significant changes were also observed upon irradiation concerning the damage of sugar rings of glycosaminoglycan molecules (Figure 1).

Figure 1.
Figure 1.

A: FT-IR representative spectrum of a non-irradiated cartilage (a) and an irradiated cartilage with a dose of 5 Gy (b). B:FT-IR spectra of cartilage from a patient with cancer (1), a patient after radiation therapy (2), and ex vivo irradiated healthy (non-arthritic, non-cancerous) cartilage (3).

Figure 2.
Figure 2.

SEM imaging morphology of arthritic cartilage (scale 0.3 mm) (A), and healthy (non-arthritic) cartilage after irradiation with a dose of 4 Gy (scale 1 mm) (B), Image J analysis of cartilage before (C) and after irradiation (D). The pixels are in a.u. and are related to surface conductivity.

Figure 3.
Figure 3.

Schematic presentation of free hydroxyl radical-glycosaminoglycan reactions (is shown only the part of disaccharide which is the monomer repeated unit of the polymer). The hydrogen atoms react at the same way, while the electrons are inert for hyaluronic acid.

The complementary investigation with Scanning Electron Microscopy illustrates well the architectural images of the cartilage surfaces. After comparison of the SEM images in the irradiated and osteoarthritis cartilage specimens (Figure 2), it was obvious that the damage caused by osteoarthritis was the same as that caused by the radiation dose. The illustrations in Figure 2 are in agreement and are correlated with the changes taking place in the infrared spectra recorded.

Discussion

Radiation-induced bone side-effects include fractures, radiation osteitis, osteolysis and osteoradionecrosis, growth plate complications, and delayed fracture-healing (3, 18). Radiation osteitis refers to a radiation-induced inflammatory response in blood vessels, bone marrow, nerve tissue and bone cells that may lead to necrosis of the bone-forming elements and fracture of trabecular and cortical bone (18). The pathogenesis of radiation osteitis is a combination of direct cell injury and radiation-induced vascular injury. Osteocytes, osteoblasts, osteoclasts, and mesenchymal cells can be injured or killed by radiation (19, 20). Furthermore, the small blood vessels of the Volkmann canals and haversian vessels may demonstrate endothelial injury, with eventual fibrosis of the vessels. Fibrosis of the periosteum and endosteum can also occur.

The fibril formation was observed fin our ex vivo irradiation of cartilage, as evidenced by the appearance of the band at 1690 cm−1. From this band it was suggested that the free hydroxyl radicals, formed by radiolysis of water reacted with collagenous proteins, by abstraction of hydrogen atoms or addition to double bonds of aminoacids. The resulting new protein radicals forming a series reactions lead to amyloid-like protein and finally to fibril formation. This process became more evident when we increased the radiation dose up to 50 Gy.

The damage induced by irradiation to cartilage matrix was more obvious when we analyzed the pictures taken from SEM analysis using ImageJ software. Image J (http://imagej.nih.gov/ij/) analysis of SEM images of cartilage before and after irradiation showed scission of the matrix induced by irradiation (Figure 2C and D).

It was suggested that these scissions are responsible for the protein unfolding/denaturation. It seems that under irradiation the folding enzymes (or foldases) are inhibited to restore the configuration of proteins during radiotherapy (21). Additionally, the high conductivity, which was observed on the surface, was a result of Na+ and Ca2+ cation deposition on the surface of the cartilage, as was found by EDX analysis. These cations appeared to have reacted with the terminal COO− units of hyaluronic acid, forming salts and thus stabilizing the damage.

The pictures in Figure 2 together with the micro-IR spectral analysis could explain the heterogeneous bone density, the fibril formation, which lead to mechanical integrity of exposed articular cartilage when patients received radiotherapy (22). Overall, radiation effects on matrix metabolism remain unclear; limited data suggest that radiation has a direct negative impact on matrix production, metabolism and breakdown in adult animal models (22). Recent preclinical evidence also suggests that radiation can induce an acute reduction in the surface mechanical properties of mouse and pig articular cartilage, specifically lowering compressive stiffness (24). A weakening of cartilage at articular surfaces in response to irradiation, specifically by altering matrix metabolism, could contribute to overall joint erosion (24).

The observed changes after irradiation in the spectral region between 4000-3000 cm−1, show also an increase of the band near 3600 cm−1, which corresponds to non-hydrogen bonded vOH. By taking into account the interaction of γ-Rays with the cartilage components and that during irradiation the water molecules of the biological cells decompose into free hydroxyl radicals (HO*), hydrogen atoms (H) and hydrated electrons (eaq−) as is shown (25): Embedded Image

Then the HO* radicals react by abstraction of hydrogen atoms from sugar moieties of glycosaminoglycans and give rise to the formation of glycosaminoglycans free radicals 1 (Figure 3).

In free hydroxyl radical-glycosaminoglycan reactions, the hydrogen atoms react in the same way, while the electrons are inert for hyaluronic acid (26, 27). The generated free radical 1 if not repaired by a hydrogen atom donor will decompose to other products. The newly-formed products show the increase of non-hydrogen bonded hydroxyl groups, in agreement with the broad and large hydroxyl infrared band in the ATR-FT-IR spectra. These reactions are also in accordance with the appearance of the new band at about 1160 cm−1, which corresponds to sugar moiety (C-O-C) absorption. The breaks of the chain length of glycosaminoglycans justify the observed reduction of hydrogen bonding, as was shown from the changes in the infrared spectral region, 4000-3000 cm−1 discussed above. Furthermore, in the presence of oxygen the free radical 1 reacts with oxygen molecules to form superoxides, which finally could lead to reduction of cartilage viscosity. These results may be taking place during arthritis development in the patients, since the morphology of arthritic cartilage is the same with the morphology which was induced after irradiation of cartilage.

In order to understand the behavior of the interaction of biological systems with γ-rays and the cartilage during radiotherapy, we have compared the IR spectra between cancerous cartilage with that from a patient who received radiotherapy together with the ex vivo irradiated cartilage at a dose of 5 Gy (Figure 1B).

As shown, the intensity of the band at about 1743 cm−1 is increased after radiotherapy and irradiation. It seems then that the peroxidation of the membrane lipids takes place during irradiation leading to aldehyde formation (12, 13). The irradiation interacting with the cartilage collagen and the cartilage cells. It seems that the peroxidation of the membrane lipids take place during irradiation leading to aldehyde formation. The cartilage cell membrane contains lipoproteins and is very important for the proper function of cartilage cells. The distraction of the cell membrane due to loss of lipoprotein content and orientation leads to dead cartilage cells with no biological and mechanical role. It is very important to notice that the aldehyde band at 1743 cm−1 was also present, but less intense, in the spectra of cancerous cartilage, suggesting that ROS (reactive oxygen species) react with the cartilage during cancer progression.

It was also observed that the bands of Amide I and Amide II absorptions shifted to lower frequencies, suggesting that the collagen changed its structure to random coil. Deconvolution of these bands showed the initiation of amyloid-like protein formation (14) and that the collagen's microarchitecture structure has failed. In conjunction with the increased local lipophilicity, which changes further the concentration of water in cartilage the mechanical viscoelastic properties of cartilage, lead to a cascade failure.

The amyloid-like proteins by losing their architecture became unable to serve their role in contribution to the forces during joint load. The cartilage fails to absorb the stresses and to share them in a larger surface in the subchondral bone. As a result the underneath subchondral bone is susceptible to stronger stresses. Microfractures and bone remodeling turn the subchondral bone to a stiffer inelastic area. On the contrary, in the case of the ex vivo irradiated healthy cartilage the amyloid proteins were the main product. This means that during the in vivo irradiation part of the damaged proteins have been repaired. We have seen also that the ratios of [AmideI]:[AmideII] increased from 1.19 for healthy to 1.45 for patients who did not receive radiotherapy and 1.58 for patients who received radiotherapy. The ratio of [AmideI]:[AmideII] was found to depend on the dose radiation starting from 1.23 for dose of 1 Gy to 1.50 up to dose of 6 Gy. Further irradiation changes completed the structure of proteins and the formation of fibrils was observed as well as other fragments and co-polymerizations. These results confirm the formation of amyloid-like proteins with predominantly β-sheet structure

These findings from ATR-FTIR spectroscopic data show that during radiotherapy there are induced lesions similar to those of cancer and aging progression. The scientists have to develop new drugs inhibiting the cleavages of the collagen and glycosaminoglycan chain cleavages which lead to a reduction in viscosity and increase the friction of cartilage. It must be noticed that inhibition of peroxidation is one of the most sought solutions to inhibit the growth of the lesions.

Conclusion

The radiation-mediated chemical damage of cartilage and the results obtained here using FT-IR spectroscopy in combination with SEM analysis showed that cartilage is very sensitive to radiation damage. Radiation induced considerable changes in the chemistry and especially in the structure of glycosaminoglycans by changing the length of the sugar chain. These scissions of glycosaminoglycan's chains may be the cause of reduction of cartilage viscosity in patients receiving radiation therapy. It was found that proteins changed their secondary structure from α-helix to random coil and finally to amyloid-like proteins, which led to fiber formation. The increase of the intensity of the aldehyde band at 1743 cm−1 indicates the magnitude of the damage induced by lipid peroxidation.

Since radiation therapy is associated with increased risk of tissue and organ complications, physicians must use additional scientific information for a better diagnostic treatment. In this respect, FT-IR spectroscopy, a non-distractive, rapid and easy-to-use method, can provide quick results and more information than histopathology, since it does not need any special preparation or decalcification for tissue analysis. Moreover, FTIR spectroscopy allows us to detect composition and biochemical changes that can be extremely subtle and located in a small area of tissue during irradiation or cancer progression.

Acknowledgements

The FT-IR and micro-FT-IR spectroscopic evaluation of cartilage samples was done at the Laboratories of LURE, Centre Universitaire, Paris-Sud, France. The Authors would like to thank Dr. P. Doumas for his assistance in using these methods.

  • Received April 2, 2016.
  • Revision received June 7, 2016.
  • Accepted July 1, 2016.

References

  1. ↵
    1. Cannon CP,
    2. Ballo MT,
    3. Zagars GK,
    4. Mirza AN,
    5. Lin PP,
    6. Lewis VO,
    7. Yasko AW,
    8. Benjamin RS,
    9. Pisters PWT
    : Complications of combined modality treatment of primary lower extremity soft-tissue sarcomas. Cancer 107: 2455-2461, 2006.
    OpenUrlCrossRefPubMed
  2. ↵
    1. Mavrogenis AF,
    2. Megaloikonomos PD,
    3. Panagopoulos GN,
    4. Papagelopoulos PJ,
    5. Theophanides T,
    6. Anastassopoulou J
    : Side Effects of Radiation in Bone and Cartilage: An FT-IR Analysis. J Long Term Eff Med Implants 25(4): 289-295, 2015.
    OpenUrlPubMed
  3. ↵
    1. Mavrogenis AF,
    2. Papagelopoulos PJ,
    3. Romantini M,
    4. Guerra G,
    5. Ruggieri P
    : Side effects of radiation in musculoskeletal oncology. J Long Term Eff Med Implants 19(4): 287-304, 2009.
    OpenUrlCrossRefPubMed
  4. ↵
    1. Pritchard MR,
    2. Horton JA,
    3. Keenawinna LS,
    4. Damron TA
    : Microarray analysis of irradiated growth plate zones following laser microdissection shows later importance of differentially expressed genes during radiorecovery. Cells Tissues Organs 192(4): 240-249, 2010.
    OpenUrlPubMed
  5. ↵
    1. Alwood JS,
    2. Kumar A,
    3. Tran LH,
    4. Wang A,
    5. Limoli CL,
    6. Globus RK
    : Low-dose, ionizing radiation and age-related changes in skeletal microarchitecture. J Aging Res 2012: 481983, 2012 [PubMed: 22570786].
    OpenUrlPubMed
  6. ↵
    1. Rutkowska E,
    2. Baker C,
    3. Nahum A
    : Mechanistic simulation of normal-tissue damage in radiotherapy-implications for dose-volume analyses. Phys Med Biol 55: 2121-2136, 2010.
    OpenUrlCrossRefPubMed
  7. ↵
    1. Konski A,
    2. Sowers M
    : Pelvic fractures following irradiation for endometrial carcinoma. Int J Rad Oncol Biol Physic 35(2): 361-367, 1996.
    OpenUrl
  8. ↵
    1. Petra M,
    2. Anastassopoulou J,
    3. Theologis T,
    4. Theophanides T
    : Synchrotron micro-FT-IR spectroscopic evaluation of normal paediatric human bone. J. Mol Structure 78: 101, 2005.
    OpenUrl
  9. ↵
    1. Theophanides T
    : Infrared Spectroscopy-Life and Biomedical Science, InTech, Europa, 2012.
  10. ↵
    1. Theophanides T
    : Infrared Spectroscopy-Anharmonicity of Biomolecules, Crosslinking of Biopolymers, Food Quality and Medical Applications, InTech, Europa, 2015.
  11. ↵
    1. Barth A,
    2. Zscherp C
    : What vibrations tell us about proteins, Quarterly Rev Bioph 35(4): 369-430, 2002.
    OpenUrl
  12. ↵
    1. Mamarelis I,
    2. Pissaridi K,
    3. Dritsa V,
    4. Kotileas P,
    5. Tsiligiris V,
    6. Anastassopoulou J
    : Oxidative stress and atherogenesis: An FT-IR spectroscopic study. In Vivo 24: 883-888, 2010.
    OpenUrlAbstract/FREE Full Text
  13. ↵
    1. Dritsa V,
    2. Pissaridi K,
    3. Koutoulakis E,
    4. Mamarelis I,
    5. Kotoulas C,
    6. Anastassopoulou J
    : An Infrared spectroscopic study of aortic valve. A possible mechanism of calcification and the role of magnesium salts. In Vivo 84: 91-98, 2014.
    OpenUrl
  14. ↵
    1. Anastassopoulou J,
    2. Kyriakidou M,
    3. Kyriazis S,
    4. Dritsa V,
    5. Kormas T
    : Protein folding and cancer. Anticancer Res 34(10): 5806-5709, 2015.
    OpenUrl
  15. ↵
    1. Theophanides T
    1. Anastassopoulou J,
    2. Kyriakidou M,
    3. Kyriazis S,
    4. Kormas T,
    5. Mavrogenis AF,
    6. Dritsa V,
    7. Kolovou P,
    8. Theophanides T
    : An FTIR Spectroscopic Study of Metastatic Cancerous Bone, In Infrared Spectroscopy-Anharmonicity of Biomolecules, Crosslinking of Biopolymers, Food Quality and Medical Applications, Theophanides T (ed), InTech, Europa, Chapt. 5, pp. 89-100, 2015.
    1. Conti C,
    2. Ferraris P,
    3. Giorgini E,
    4. Rubini C,
    5. Sabbatini S,
    6. Tosi G,
    7. J. Anastassopoulou J,
    8. Arapantoni P,
    9. Boukaki E,
    10. Theophanides T,
    11. Valavanis C
    : FT-IR Microimaging Spectroscopy: Discrimination between healthy and neoplastic human colon tissues. J MolStruc 881: 46-51, 2008.
    OpenUrl
  17. ↵
    1. Anastassopoulou J,
    2. Boukaki E,
    3. Conti E,
    4. Ferraris P,
    5. Giorgini E,
    6. Rubini CS,
    7. Sabbatini S,
    8. Theophanides T,
    9. Tosi G
    : Microimaging FT-IR spectroscopy on pathological breast tissues Vibrational Spectroscopy 51: 270-275, 2009.
    OpenUrl
  18. ↵
    1. Ewing J
    : Radiation osteitis. Acta Radiol 6: 399-412, 1926.
    OpenUrlCrossRef
  19. ↵
    1. Mitchell MJ,
    2. Logan MP
    : Radiation-induced changes in bone. Radiographics 18: 1125-1136, 1998.
    OpenUrlCrossRefPubMed
  20. ↵
    1. Dalinka MK,
    2. Mazzeo VP Jr..
    : Complications of radiation therapy. Crit Rev Diagn Imaging 23(3): 235-267, 1985.
    OpenUrlPubMed
  21. ↵
    1. Daniel N,
    2. Hebert DN,
    3. Molinari M
    : In and Out of the ER: Protein Folding, Quality Control, Degradation, and Related Human Diseases. Physiol Rev 87: 1377-1408, 2007.
    OpenUrlAbstract/FREE Full Text
  22. ↵
    1. Willey JS,
    2. Long DL,
    3. Vanderman KS,
    4. Loeser RF
    : Ionizing radiation causes active degradation and reduces matrix synthesis in articular cartilage. Int J Radiat Biol 89(4): 268-277, 2013.
    OpenUrlPubMed
    1. Kolar J,
    2. Vrabec R,
    3. Chyba J
    : Arthropathies after irradiation. J Bone Joint Surg Am 49(6): 1157-1166, 1967.
    OpenUrlAbstract/FREE Full Text
  24. ↵
    1. Hugenberg ST,
    2. Myers SL,
    3. Brandt KD
    : Suppression of glycosaminoglycan synthesis by articular cartilage, but not of hyaluronic acid synthesis by synovium, after exposure to radiation. Arthriti Rheum 32(4): 468-474, 1989.
    OpenUrl
  25. ↵
    1. Spins JW,
    2. Woods RJ
    : An Introduction to Radiation Chemistry, John Wiley & Sons, New York, London, 2nd ed., 1976.
  26. ↵
    1. Greenwald RA,
    2. Moy WW
    : Effect of oxygen-derived free radicals on hyaluronic acid. Arthritis Rheum 24(4): 455-463, 1980.
    OpenUrl
  27. ↵
    1. Myint P,
    2. Deeble DJ,
    3. Beaumont PC,
    4. Blake SM,
    5. Phillips GO
    : The reactivity of various free radicals with hyaluronic acid: steady-state and pulse radiolysis studies. Biochim Biophys Acta 925: 194-202, 1987.
    OpenUrlPubMed
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An FT-IR Spectral Analysis of the Effects of γ-Radiation on Normal and Cancerous Cartilage
MARIA KYRIAKIDOU, ANDREAS F. MAVROGENIS, STYLIANOS KYRIAZIS, ATHINA MARKOUIZOU, THEOPHILE THEOPHANIDES, JANE ANASTASSOPOULOU
In Vivo Sep 2016, 30 (5) 599-604;
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