M Z Kastyak Chemical characterization and imaging of creatine deposits in human CNS tissues
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1 Introduction ... 14
1.1 Neurodegenerative disorders ... 15
1.1.1 Central Nervous System (CNS)... 16
1.1.2 Etiology of neurodegenerative diseases... 21
1.1.3 Amyotrophic Lateral Sclerosis ... 23
1.1.4 Deposits in ALS... 24
1.2 Creatine and phosphocreatine system ... 26
1.2.1 Creatine/phosphocreatine system physiological role... 26
1.2.2 Creatine in health and disease... 28
1.3 CNS tissues characterization and imaging ... 29
1.4 Goals... 30
2 Materials and Methods ... 32
2.1 Electromagnetic radiation... 32
2.2 Synchrotron radiation ... 35
2.3 FTIR spectroscopy ... 36
2.3.1 Infrared radiation ... 36
2.3.2 IR radiation- matter interaction... 36
2.3.3 IR spectra ... 38 2.4 FTIR instrumentation ... 40 2.4.1 IR Source ... 40 2.4.2 Michelson Interferometr ... 41 2.4.3 Detectors ... 44 2.4.4 Working modes... 44
2.5 Fourier Transform Infrared spectromicroscopy ... 46
2.6 X-Ray Fluorescence ... 48
2.6.1 X-Ray absorption and X-Ray Fluorescence. ... 48
2.7 Data aquisition and analysis ... 52
2.7.1 FTIR measurements... 52
M Z Kastyak Chemical characterization and imaging of creatine deposits in human CNS tissues
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2.8 Sample preparation... 57
3 Results ... 59
3.1 Imaging of CNS samples... 59
3.1.1 White microscope images... 59
3.1.2 CNS tissue FTIR maps ... 60
3.2 Pigmented creatine deposits found in ALS samples ... 70
3.2.1 Discovery of pigmented creatine deposits ... 70
3.2.2 Spotlight survey ... 72
3.2.3 Comparison of FTIR maps and conventional staining method ... 76
3.2.4 Light polarization and creatine deposits detection ... 77
3.2.5 Detailed FTIR maps for pigmented and non-pigmented creatine deposits .... 85
3.2.6 XRF analysis of creatine pigmented deposits... 88
4 Discussion ... 101
4.1 Pigmented creatine deposits ... 101
4.2 Tissue artefacts: advantage or disadvantage?... 105
4.3 Instrumentation influence on FTIR spectra... 107
5 Conclusions ... 110
6 Future work ... 111
7 Appendix 1 ... 112
