Biomedical Spectroscopy and Imaging - Volume 2, issue 1

Authors: Fendt, Sarah-Maria | Stephanopoulos, Gregory

Article Type: Research Article

Abstract: Metabolism is the functional interconnection between the genome, transcriptome and proteome with the cellular phenotype. Thus, understanding metabolism is of great interest in various research areas ranging from metabolic engineering to the biomedical research field. Here we frame, based on recent advances in elucidating various metabolic nodes, a global perspective of our current understanding of metabolism.

Keywords: Metabolism, genome, proteome, transcriptome, high-throughput mass spectrometry

DOI: 10.3233/BSI-120032

Citation: Biomedical Spectroscopy and Imaging, vol. 2, no. 1, pp. 1-8, 2013

Authors: Pan, Xiaoyan | Wilson, Martin | McConville, Carmel | Arvanitis, Theodoros N. | Kauppinen, Risto A. | Peet, Andrew C.

Article Type: Research Article

Abstract: Active biogenesis of cytoplasmic lipid droplets (LDs) is reported in different types of cancer cells. LDs are linked to cancer cell proliferation, apoptosis and differentiation. The chemical nature of lipids in LDs is poorly understood and revealing their chemical composition may provide novel information of lipid metabolism in cancers. Gradient ultracentrifugation was performed to isolate LDs from five nervous system tumour cell lines. Nile red staining was used to estimate the size of LDs and validate the isolation procedure. 1 H NMR spectroscopy was performed from the chloroform/methanol extracts of whole cells and the isolated LDs. NMR lipid signal …intensity from different lipid species was measured to compare the lipid compositions. The average diameter of LDs in cancer cells was 0.21±0.02 μm, with a widely varying size range up to 1.48 μm. 1 H NMR spectroscopic analysis revealed that the LDs contain phosphatidylcholine, cholesterol and cholesterol ester with saturated, mono-unsaturated and polyunsaturated fatty acid species. The content of the isolated LDs differed between the tumor cell lines with variability seen in unsaturated fatty acids, cholesterol and lipids containing choline head groups however the mean fatty acid chain length remained similar across the cell lines. The lipid composition of LDs was also found to be different from whole cell extracts. In conclusion, we have shown that the composition of LDs differs between tumour cell lines, suggesting a functional link between these structures and cancer specific pathways. Show more

Keywords: Lipid droplets, ^1H NMR, isolation

DOI: 10.3233/BSI-130035

Citation: Biomedical Spectroscopy and Imaging, vol. 2, no. 1, pp. 9-19, 2013

Authors: Rathnayaka, Kanchana | Momot, Konstantin I. | Coulthard, Alan | Volp, Andrew | Sahama, Tony | Schütz, Michael A. | Schmutz, Beat

Article Type: Research Article

Abstract: The current gold standard for the design of orthopaedic implants is 3D models of long bones obtained using computed tomography (CT). However, high-resolution CT imaging involves high radiation exposure, which limits its use in healthy human volunteers. Magnetic resonance imaging (MRI) is an attractive alternative for the scanning of healthy human volunteers for research purposes. Current limitations of MRI include difficulties of tissue segmentation within joints and long scanning times. In this work, we explore the possibility of overcoming these limitations through the use of MRI scanners operating at a higher field strength. We quantitatively compare the quality of …anatomical MR images of long bones obtained at 1.5 T and 3 T and optimise the scanning protocol of 3 T MRI. FLASH images of the right leg of five human volunteers acquired at 1.5 T and 3 T were compared in terms of signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). The comparison showed a relatively high CNR and SNR at 3 T for most regions of the femur and tibia, with the exception of the distal diaphyseal region of the femur and the mid-diaphyseal region of the tibia. This was accompanied by an ~65% increase in the longitudinal spin relaxation time (T1 ) of the muscle at 3 T compared to 1.5 T. The results suggest that MRI at 3 T may be able to enhance the segmentability and potentially improve the accuracy of 3D anatomical models of long bones, compared to 1.5 T. We discuss how the total imaging times at 3 T can be kept short while maximising the CNR and SNR of the images obtained. Show more

Keywords: Anatomical MRI, long bones, spin relaxation times, SNR, CNR

DOI: 10.3233/BSI-120030

Citation: Biomedical Spectroscopy and Imaging, vol. 2, no. 1, pp. 21-35, 2013

Authors: Muntean, Cristina M. | Bratu, Ioan | Bogdan, Diana

Article Type: Research Article

Abstract: In this work the Raman total half band widths of five nucleic acids nitrogenous bases (adenine, guanine, cytosine, thymine and uracil) have been measured, respectively. Raman scattering can be used to study the fast subpicosecond dynamics of purinic and pyrimidinic nucleic acids bases in solid state. The dependencies of the total half band widths and of the corresponding global relaxation times, on atomic groups and on the type of free nucleic acids bases, are reported. In our study, the full widths at half-maximum (FWHMs) for the Raman bands of nucleic acids bases, are typically in the wavenumber range …from 9.5 to 22 cm−1 . Besides, it can be observed that molecular relaxation processes studied in this work, have a global relaxation time value smaller than 1.06 ps and larger than 0.46 ps. We have found that the band centered at 941 cm−1 of adenine, the profiles near 1232 cm−1 , 1678 cm−1 , in the case of guanine, the band around 1116 cm−1 attributed to cytosine, the profiles at 1490, 1673 cm−1 attributed to thymine and several Raman bands corresponding to atomic groups in uracil, respectively, are suitable for further studying the dynamical behavior of molecular fragments in nucleic acids bases. Show more

Keywords: Nucleic acids bases, Raman spectroscopy, full width at half-maximum (FWHM), subpicosecond global relaxation time

DOI: 10.3233/BSI-120033

Citation: Biomedical Spectroscopy and Imaging, vol. 2, no. 1, pp. 37-49, 2013

Authors: Srajer, Johannes | Schwaighofer, Andreas | Nowak, Christoph

Article Type: Review Article

Abstract: Surface-enhanced Raman spectroscopy (SERS) is an analytical technique exploiting plasmonic effects that enhance sensitivity significantly, compared to conventional Raman spectroscopy. Progress in nanotechnology led to new fabrication methods for nanostructures and nanoparticles over the last decade. Besides increased comprehension of mechanisms that cause the signal enhancement, computational methods have been developed to tailor analyte-specific nanostructures efficiently. The ability to control the size, shape, and material of surfaces has facilitated the widespread application of SERS in biomedical analytics and clinical diagnostics. In this review, a brief excerpt of such SERS applications is shown, with special focus on cancer diagnostics, glucose detection …and in vivo imaging applications. Simulation techniques are discussed to show that electro-dynamic theory can be used to predict the characteristics of nanostructure arrangements. Different fabrication methods, such as nanoparticle synthesis, their immobilization and lithographic methods are reviewed in brief. Show more

Keywords: Surface-enhanced Raman spectroscopy, SERS, glucose, cancer, in vivo, nanostructure fabrication, lithography, nanoparticles, plasmonics, Mie theory, DDA, FDTD, imaging

DOI: 10.3233/BSI-120034

Citation: Biomedical Spectroscopy and Imaging, vol. 2, no. 1, pp. 51-71, 2013

Authors: Severcan, Feride | Haris, Parvez I. | Aksoy, Ceren | Simsek Ozek, Nihal

Article Type: Research Article

Abstract: Vibrational spectroscopy has a great potential in diagnosis and screening with increasing number of applications in biological and biomedical fields, food and environmental sciences and forensic area. This review focuses on the historical background and recent developments related to the use of this technique in various areas of diagnosis and screening.

Keywords: Vibrational spectroscopy, diagnosis, screening

DOI: 10.3233/BSI-130036

Citation: Biomedical Spectroscopy and Imaging, vol. 2, no. 1, pp. 73-81, 2013