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Papers by Keith R Bambery

Radiation Research

Synchrotron radiation-Fourier transform infrared (SR-FTIR) microscopy coupled with multivariate d... more Synchrotron radiation-Fourier transform infrared (SR-FTIR) microscopy coupled with multivariate data analysis was used as an independent modality to monitor the cellular bystander effect. Single, living prostate cancer PC-3 cells were irradiated with various numbers of protons, ranging from 50-2,000, with an energy of either 1 or 2 MeV using a proton microprobe. SR-FTIR spectra of cells, fixed after exposure to protons and nonirradiated neighboring cells (bystander cells), were recorded. Spectral differences were observed in both the directly targeted and bystander cells and included changes in the DNA backbone and nucleic bases, along with changes in the protein secondary structure. Principal component analysis (PCA) was used to investigate the variance in the entire data set. The percentage of bystander cells relative to the applied number of protons with two different energies was calculated. Of all the applied quantities, the dose of 400 protons at 2 MeV was found to be the most...

2001 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. No.01CH37225), 2001

ABSTRACT

Biophysical Journal, 2014

ABSTRACT The ability to accurately detect DNA both quantitatively and qualitatively inside cells ... more ABSTRACT The ability to accurately detect DNA both quantitatively and qualitatively inside cells using Fourier transform infrared (FTIR) spectroscopy has been disputed. Recently, we have demonstrated that the variability of DNA absorptions is due to the dehydrated nature of biological samples prepared for FTIR spectroscopic measurement [1]. We have further demonstrated that in the dehydrated and fixed state DNA in cells assumes an A-DNA conformation instead of the native B-DNA form. Importantly, as well as being detected in eukaryotes which were invariably destroyed during dehydration, this B-A DNA transition has also been observed in desiccation-resistant, dormant bacteria and the native B- conformation has been detected upon rehydration of these cells.

2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena, 2003

ABSTRACT

Synchrotron Radiation News, 2014

ABSTRACT The Seventh International Workshop on Infrared Microscopy and Spectroscopy with Accelera... more ABSTRACT The Seventh International Workshop on Infrared Microscopy and Spectroscopy with Accelerator-Based Sources (WIRMS 2013) was hosted by the Australian Synchrotron at the Mantra Resort in the coastal town of Lorne on the Great Ocean Road west of Melbourne, Australia, from November 10 to 14, 2013. In common with previous WIRMS meetings, the conference saw a coming together of staff and users from the world's synchrotron and free electron laser facilities, several of which were represented at the meeting for the first time. Scientific highlights of WIRMS 2013 included reports on FTIR spectro-microtomography, near-field infrared imaging, and cultural heritage applications.

PloS one, 2015

Fourier Transform Infrared (FTIR) micro-spectroscopy is an emerging technique for the biochemical... more Fourier Transform Infrared (FTIR) micro-spectroscopy is an emerging technique for the biochemical analysis of tissues and cellular materials. It provides objective information on the holistic biochemistry of a cell or tissue sample and has been applied in many areas of medical research. However, it has become apparent that how the tissue is handled prior to FTIR micro-spectroscopic imaging requires special consideration, particularly with regards to methods for preservation of the samples. We have performed FTIR micro-spectroscopy on rodent heart and liver tissue sections (two spectroscopically very different biological tissues) that were prepared by desiccation drying, ethanol substitution and formalin fixation and have compared the resulting spectra with that of fully hydrated freshly excised tissues. We have systematically examined the spectra for any biochemical changes to the native state of the tissue caused by the three methods of preparation and have detected changes in infr...

Physical chemistry chemical physics : PCCP, Jan 10, 2014

Surface enhanced Raman scattering (SERS) is a powerful tool with great potential to provide impro... more Surface enhanced Raman scattering (SERS) is a powerful tool with great potential to provide improved bio-sensing capabilities. The current 'gold-standard' method for diagnosis of malaria involves visual inspection of blood smears using light microscopy, which is time consuming and can prevent early diagnosis of the disease. We present a novel surface-enhanced Raman spectroscopy substrate based on gold-coated butterfly wings, which enabled detection of malarial hemozoin pigment within lysed blood samples containing 0.005% and 0.0005% infected red blood cells.

ABSTRACT Mesenchymal stem cells (MSC) in the human hair follicle have been shown to be multi-pote... more ABSTRACT Mesenchymal stem cells (MSC) in the human hair follicle have been shown to be multi-potent and take part in cutaneous wound healing by providing new fibroblasts. They can be found in the dermal papilla (DP) and the connective tissue sheath (CTS) which surrounds the hair follicle. Since they are easily accessible and are abundant, their harvesting is highly desired in regenerative medicine. Their isolation and characterization is however hindered by the lack of known specific antigens for identifying them, apart from the expression of nestin protein which is an intermediate filament also found in neuronal stem cells. Focal plane array (FPA) – fourier transform infrared (FTIR) spectroscopy provides a label-free and non-destructive method for obtaining macromolecular information from biological samples. As molecular bonds absorb infrared at specific wavelengths, and the level of absorbance depends on the quantity of the specific bonding, measurements of infrared absorbance provides qualitative and quantitative results of bio-molecules present in the sample. In order to identify and to characterize the MSC, we applied FPA-FTIR to map scan over the centre of the hair bulb, over the DP and the CTS below the DP. The scanned area is sub-divided into 8192 small sub-sections, with each section approximating the size of a DP cell (5–10 lm) in situ. An FTIR spectrum is recorded in each sub-section, forming a hyper-spectral data cube. This hyper-spectral data cube was analyzed using the chemometric technique unsupervised hierarchical clustering analysis. Clustering individual spectra based on their chemical similarities. From this, bio-molecular information in each region could be extrapolated and de-convoluted to identify pheno-typical traits. Based on the current knowledge on mesenchymal stem cells from the literature and from our nestin immunostaining results, we postulate that the MSC in the DP should be centered in the DP, contain high level of fatty acids (lipid reserve for when proliferation is required) and high level of proteins (signaling molecules and transcription factors are required to maintain stem cell state) and may be identified by the presence of phosphates (PO2-) related to DNA methylation state. By performing hierarchical clustering analyses on the spectra using different criteria, producing spectral clusters, and finding the region of high fatty acids and proteins, we successfully singled out an area which is likely to be the MSC-containing region within the DP. Individual spectra can be analyzed further for stem cell related features. We aim to verify this method as a valid way to narrowing down an MSC-containing region by staining the FTIR map scanned sample using anti-nestin antibody.

Radiation Research

Synchrotron radiation-Fourier transform infrared (SR-FTIR) microscopy coupled with multivariate d... more Synchrotron radiation-Fourier transform infrared (SR-FTIR) microscopy coupled with multivariate data analysis was used as an independent modality to monitor the cellular bystander effect. Single, living prostate cancer PC-3 cells were irradiated with various numbers of protons, ranging from 50-2,000, with an energy of either 1 or 2 MeV using a proton microprobe. SR-FTIR spectra of cells, fixed after exposure to protons and nonirradiated neighboring cells (bystander cells), were recorded. Spectral differences were observed in both the directly targeted and bystander cells and included changes in the DNA backbone and nucleic bases, along with changes in the protein secondary structure. Principal component analysis (PCA) was used to investigate the variance in the entire data set. The percentage of bystander cells relative to the applied number of protons with two different energies was calculated. Of all the applied quantities, the dose of 400 protons at 2 MeV was found to be the most...

2001 Annual Report Conference on Electrical Insulation and Dielectric Phenomena (Cat. No.01CH37225), 2001

ABSTRACT

Biophysical Journal, 2014

ABSTRACT The ability to accurately detect DNA both quantitatively and qualitatively inside cells ... more ABSTRACT The ability to accurately detect DNA both quantitatively and qualitatively inside cells using Fourier transform infrared (FTIR) spectroscopy has been disputed. Recently, we have demonstrated that the variability of DNA absorptions is due to the dehydrated nature of biological samples prepared for FTIR spectroscopic measurement [1]. We have further demonstrated that in the dehydrated and fixed state DNA in cells assumes an A-DNA conformation instead of the native B-DNA form. Importantly, as well as being detected in eukaryotes which were invariably destroyed during dehydration, this B-A DNA transition has also been observed in desiccation-resistant, dormant bacteria and the native B- conformation has been detected upon rehydration of these cells.

2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena, 2003

ABSTRACT

Synchrotron Radiation News, 2014

ABSTRACT The Seventh International Workshop on Infrared Microscopy and Spectroscopy with Accelera... more ABSTRACT The Seventh International Workshop on Infrared Microscopy and Spectroscopy with Accelerator-Based Sources (WIRMS 2013) was hosted by the Australian Synchrotron at the Mantra Resort in the coastal town of Lorne on the Great Ocean Road west of Melbourne, Australia, from November 10 to 14, 2013. In common with previous WIRMS meetings, the conference saw a coming together of staff and users from the world's synchrotron and free electron laser facilities, several of which were represented at the meeting for the first time. Scientific highlights of WIRMS 2013 included reports on FTIR spectro-microtomography, near-field infrared imaging, and cultural heritage applications.

PloS one, 2015

Fourier Transform Infrared (FTIR) micro-spectroscopy is an emerging technique for the biochemical... more Fourier Transform Infrared (FTIR) micro-spectroscopy is an emerging technique for the biochemical analysis of tissues and cellular materials. It provides objective information on the holistic biochemistry of a cell or tissue sample and has been applied in many areas of medical research. However, it has become apparent that how the tissue is handled prior to FTIR micro-spectroscopic imaging requires special consideration, particularly with regards to methods for preservation of the samples. We have performed FTIR micro-spectroscopy on rodent heart and liver tissue sections (two spectroscopically very different biological tissues) that were prepared by desiccation drying, ethanol substitution and formalin fixation and have compared the resulting spectra with that of fully hydrated freshly excised tissues. We have systematically examined the spectra for any biochemical changes to the native state of the tissue caused by the three methods of preparation and have detected changes in infr...

Physical chemistry chemical physics : PCCP, Jan 10, 2014

Surface enhanced Raman scattering (SERS) is a powerful tool with great potential to provide impro... more Surface enhanced Raman scattering (SERS) is a powerful tool with great potential to provide improved bio-sensing capabilities. The current 'gold-standard' method for diagnosis of malaria involves visual inspection of blood smears using light microscopy, which is time consuming and can prevent early diagnosis of the disease. We present a novel surface-enhanced Raman spectroscopy substrate based on gold-coated butterfly wings, which enabled detection of malarial hemozoin pigment within lysed blood samples containing 0.005% and 0.0005% infected red blood cells.

ABSTRACT Mesenchymal stem cells (MSC) in the human hair follicle have been shown to be multi-pote... more ABSTRACT Mesenchymal stem cells (MSC) in the human hair follicle have been shown to be multi-potent and take part in cutaneous wound healing by providing new fibroblasts. They can be found in the dermal papilla (DP) and the connective tissue sheath (CTS) which surrounds the hair follicle. Since they are easily accessible and are abundant, their harvesting is highly desired in regenerative medicine. Their isolation and characterization is however hindered by the lack of known specific antigens for identifying them, apart from the expression of nestin protein which is an intermediate filament also found in neuronal stem cells. Focal plane array (FPA) – fourier transform infrared (FTIR) spectroscopy provides a label-free and non-destructive method for obtaining macromolecular information from biological samples. As molecular bonds absorb infrared at specific wavelengths, and the level of absorbance depends on the quantity of the specific bonding, measurements of infrared absorbance provides qualitative and quantitative results of bio-molecules present in the sample. In order to identify and to characterize the MSC, we applied FPA-FTIR to map scan over the centre of the hair bulb, over the DP and the CTS below the DP. The scanned area is sub-divided into 8192 small sub-sections, with each section approximating the size of a DP cell (5–10 lm) in situ. An FTIR spectrum is recorded in each sub-section, forming a hyper-spectral data cube. This hyper-spectral data cube was analyzed using the chemometric technique unsupervised hierarchical clustering analysis. Clustering individual spectra based on their chemical similarities. From this, bio-molecular information in each region could be extrapolated and de-convoluted to identify pheno-typical traits. Based on the current knowledge on mesenchymal stem cells from the literature and from our nestin immunostaining results, we postulate that the MSC in the DP should be centered in the DP, contain high level of fatty acids (lipid reserve for when proliferation is required) and high level of proteins (signaling molecules and transcription factors are required to maintain stem cell state) and may be identified by the presence of phosphates (PO2-) related to DNA methylation state. By performing hierarchical clustering analyses on the spectra using different criteria, producing spectral clusters, and finding the region of high fatty acids and proteins, we successfully singled out an area which is likely to be the MSC-containing region within the DP. Individual spectra can be analyzed further for stem cell related features. We aim to verify this method as a valid way to narrowing down an MSC-containing region by staining the FTIR map scanned sample using anti-nestin antibody.