Physics Commons^™

Determination Of Spectral Markers Of Cytotoxicity And Genotoxicity Using In Vitro Raman Microspectroscopy: Cellular Responses To Polyamidoamine Dendrimer Exposure, Esen Efeoglu, Alan Casey, Hugh Byrne

Articles

Although consumer exposure to nanomaterials is ever increasing, with potential increased applications in areas such as drug and/or gene delivery, contrast agents and diagnosis, determination of cyto- and geno- toxic effect of nanomaterials on human health and the environment still remains challenging. Although many techniques have been established and adapted to determine the cytotoxicity and genotoxicity of nano-sized materials, these techniques remain limited by the number of assays required, total cost, use of labels and they struggle to explain the underlying interaction mechanisms. In this study, Raman microspectroscopy is employed as an in vitro label free high content screening technique …

Recent Advances In Optical Diagnosis Of Oral Cancers: Review And Future Perspectives, Ola Ibrahim, Hugh Byrne, Fiona Lyng, Surya Singh, Jopi Mikkonen, Arto Koistinen, Arja Kullaa

Articles

Optical diagnosis techniques offer several advantages over traditional approaches, including objectivity, speed and cost, and these label-free, non-invasive methods have the potential to change the future work-flow of cancer management. The oral cavity is particularly accessible and thus such methods may serve as alternate/adjunct tools to traditional methods. Recently, in vivo human clinical studies have been initiated with a view to clinical translation of such technologies. A comprehensive review of optical methods in oral cancer diagnosis is presented. Following an introduction to the epidemiology and aetiological factors associated with oral cancers currently employed diagnostic methods and their limitations are presented. …

Irish Healthcare Staff - Smoking, Training And Activity In Treatment Of Tobacco Dependence - An Online Survey, Sheila Keogan

Other Resources

INTRODUCTION Ireland has strong tobacco control legislation but must get smokers to stop if the national plan of having a smoking prevalence of 5% by the year 2025 is possible. Involving all healthcare staff in this effort is regarded as important. We surveyed the present situation. METHODS An online survey was conducted of 1257 healthcare staff; 520 nurses, 440 doctors, 297 dentists in 2014. The sample was accessed with the help of the Irish Nurses and Midwifes Organisation (INMO), Irish Medical Organisation (IMO) and the Irish Dental Association (IDA). The questionnaire addressed individual smoking habits and attitudes, training and practice …

Screening For Peripheral Arterial Disease And Carotid Artery Disease In Patients With Abdominal Aortic Aneurysm, Cleona Gray, Patrick J. Goodman, Paul Cullen, Stephen Badger, Kevin O'Malley, Martin K. O'Donohoe, Ciarán O. Mcdonnell

Articles

Screening for concomitant atherosclerotic disease is important in cardiovascular risk reduction. This study assessed the prevalence of carotid artery disease (CAD) and peripheral arterial disease (PAD) in patients with known abdominal aortic aneurysms (AAAs). All patients with AAA attending the vascular laboratory between the January 1, 2007, and December 31, 2009, were eligible for a carotid ultrasound and measurement of ankle brachial indices. A total of 389 (305 males) patients were identified on the AAA surveillance program with a mean (±standard deviation) age of 76 (±8) years. The mean age of the males was 75.4 (±7.8) years, and the mean …

Endovascular Aneurysm Repair Increases Aortic Arterial Stiffness When Compared To Open Repair Of Abdominal Aortic Aneurysms, Cleona Gray, Patrick J. Goodman, Stephen Badger, M. Kevin O'Malley, Martin K. O'Donohoe, Ciarán O. Mcdonnell

Articles

Objectives: The initial survival advantage seen with endovascular aneurysm repair (EVAR) over open repair does not persist in the long term. Pulse wave velocity (PWV) is a measure of arterial stiffness, and increased PWV is an independent risk factor for increased cardiovascular morbidity and mortality. This prospective comparative pilot study examined the effect of implantation of an aortic graft on PWV in patients undergoing open or endovascular aortic aneurysm repair. Patients and Methods: Thirty-four patients (15 open and 19 EVAR) were recruited. Patient demographics were similar in both the groups. Pulse wave velocity was calculated for all patients …

Raman Micro Spectroscopy For In Vitro Drug Screening: Subcellular Localisation And Interactions Of Doxorubicin, Zeineb Farhane, Franck Bonnier, Alan Casey, Hugh Byrne

Articles

Vibrational spectroscopy, including Raman spectroscopy, has been widely used over the last few years to explore potential biomedical applications. Indeed, Raman spectroscopy has been demonstrated to be a powerful non-invasive tool in cancer diagnosis and monitoring. In confocal microscopic mode, the technique is also a molecularly specific analytical tool with optical resolution which has potential applications in subcellular analysis of biochemical processes, and therefore as an in vitro screening tool of the efficacy and mode of action of, for example, chemotherapeutic agents.

In order to demonstrate and explore the potential in this field, established, model chemotherapeutic agents can be valuable. …

Optical Diagnostics – Spectropathology For The Next Generation, Malgorzata Baranska, Hugh Byrne

Articles

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Spectropathology For The Next Generation: Quo Vadis?, Hugh Byrne, Malgorzata Baranska, Gerwin J. Pupples, Nick Stone, Bayden Wood, Kathleen M. Gough, Peter Lasch, Phil Heraud, Josep Sulé-Suso, Ganesh Sockalingum

Articles

Although the potential of vibrational spectroscopy for biomedical applications has been well demonstrated, translation into clinical practice has been relatively slow. This Editorial assesses the challenges facing the field and the potential way forward. While many technological challenges have been addressed to date, considerable effort is still required to gain acceptance of the techniques among the medical community, standardise protocols, extend to a clinically relevant scale, and ultimately assess the health economics underlying clinical deployment. National and international research networks can contribute much to technology development and standardisation. Ultimately, large-scale funding is required to engage in clinical trials and instrument …

Vibrational Microspectroscopy For Cancer Screening, Fiona Lyng, Ines Ramos, Ola Ibrahim, Hugh Byrne

Articles

Vibrational spectroscopy analyses vibrations within a molecule and can be used to characterise a molecular structure. Raman spectroscopy is one of the vibrational spectroscopic techniques, in which incident radiation is used to induce vibrations in the molecules of a sample, and the scattered radiation may be used to characterise the sample in a rapid and non-destructive manner. Infrared (IR) spectroscopy is a complementary vibrational spectroscopic technique based on the absorption of IR radiation by the sample. Molecules absorb specific frequencies of the incident light which are characteristic of their structure. IR and Raman spectroscopy are sensitive to subtle biochemical changes …

Multivariate Statistical Methodologies Applied In Biomedical Raman Spectroscopy: Assessing The Validity Of Partial Least Squares Regression Using Simulated Model Datasets, Mark E. Keating, Haq Nawaz, Franck Bonnier, Hugh Byrne

Articles

Raman spectroscopy is fast becoming a valuable analytical tool in a number of biomedical scenarios, most notably disease diagnostics. Importantly, the technique has also shown increasing promise in the assessment of drug interactions on a cellular and subcellular level, particularly when coupled with multivariate statistical analysis. However, an important consideration, both with Raman spectroscopy and the associated statistical methodologies, is the accuracy of these techniques and more specifically the sensitivities which can be achieved and ultimately the limits of detection of the various methods. The purpose of this study is thus the construction of a model simulated data set with …

Refraction In Mozambique: Evaluations Of Practice And Development Of Competency Frameworks For Eye Care Personnel, Kajal Shah

Doctoral

Purpose The development of competency- based education for optometrists and mid-level eye-care personnel has been identified as an important component in the elimination of avoidable blindness and vision impairment. The Mozambique Eye care Project (MEP) is a multi-institutional collaboration, which seeks to facilitate greater access to training in eye health professions, which will ultimately contribute to providing affordable and accessible eye care within the public health system in Mozambique. An important tenet of the MEP is to develop and enhance the refraction training of all existing (ophthalmic technicians) and new eye care personnel (four-year training of optometrists and eighteen-month training …

Raman Microspectroscopy For The Early Detection Of Pre-Malignant Changes In Cervical Tissue, Nosheen Rashid, Haq Nawaz, Kelvin W. Poon, Franck Bonnier, Salih Bakhiet, Cara Martin, John O'Leary, Hugh Byrne, Fiona Lyng

Articles

Cervical cancer is the third most common cancer affecting women worldwide. The mortality associated with cervical cancer can, however, be significantly reduced if the disease is detected at the pre-malignant stage. The aim of this study was to evaluate the potential of Raman microspectroscopy for elucidation of the biochemical changes associated with the pre-malignant stages of cervical cancer. Formalin fixed paraffin preserved tissue sections from cervical biopsies classified as negative for intraepithelial lesion and malignancy (NILM), low grade squamous intraepithelial lesion (LSIL) or high grade squamous intraepithelial lesion (HSIL) were analysed by Raman spectral mapping. Raman mapping, with K-Means Cluster …

Quantitative Assessment Of Blood Coagulation By Cold Atmospheric Plasma, Caitlin Heslin, Daniela Boehm, Vladimir Milosavljevic, Michelle Laycock, Patrick Cullen, Paula Bourke

Articles

Cold atmospheric plasma (CAP) is produced by ionizing a chosen gas, thereby creating charged and reactive species. The reactive species generated are capable of inducing a range of biomedically relevant interactions including blood coagulation. However, the underlying biochemical processes of plasma-assisted blood coagulation are largely unknown, and data quantifying blood clot formation or the impact of system parameters on the intensity of the blood clot are scarce. In this study, blood coagulation was quantified by measuring hemoglobin absorbance. System parameters of the kINPen plasma jet were investigated and compared, including treatment time, distance from the plasma source and gas flow …

Improved Protocols For Vibrational Spectroscopic Analysis Of Body Fluids, Franck Bonnier, François Petitjean, Matthew Baker, Hugh Byrne

Articles

The applications of vibrational spectroscopy to the examination of human blood serum are explored. Although FTIR spectra can be recorded in aqueous solutions at (gelatin) concentrations as low as 100mg/L, the high-wavenumber region remains obscured by water absorption. Using Raman spectroscopy, high quality spectra of gelatine solutions as low as 10mg/L can be achieved, also covering the high-wavenumber regions. In human serum, spectral profiles are weak and partially obscured by water features. Dried deposits are shown to be physically and chemically inhomogeneous resulting in reduced measurement reproducibility. Concentration of the serum using commercially available centrifugal filter devices results in an …

Vibrational Spectroscopy: Disease Diagnostics And Beyond, Hugh Byrne, Kamila Ostrowska, Haq Nawaz, Jennifer Dorney, Aidan Meade, Franck Bonnier, Fiona Lyng

Books/Book Chapters

Summary

This chapter outlines some developments in the applications of vibrational spectroscopy for disease diagnostics and demonstrates how the applications of the spectroscopic techniques can be extended to the analysis and evaluation of disease aetiology and the mechanisms of interaction and the cellular and subcellular responses to, for example chemotherapeutic agents and nanoparticles. The primary emphasis is on Raman spectroscopy, although some examples are based on infrared absorption spectroscopy. The studies presented are chosen to illustrate how a range of multivariate analytical techniques can be employed to maximize the potential benefits of the complex spectral information obtained from tissue or …

Raman Spectroscopic Analysis Of Human Skin Tissue Sections Ex-Vivo: Evaluation Of The Effects Of Tissue Processing And Dewaxing, Syed Mehmood Ali, Franck Bonnier, Ali Tfayli, Helen Lambkin, Kathleen Flynn, Vincent Mcdonagh, Claragh Healy, Thomas Lee, Fiona Lyng, Hugh Byrne

Articles

Raman spectroscopy coupled with K-means clustering analysis (KMCA) is employed to elucidate the biochemical structure of human skin tissue sections, and the effects of tissue processing. Both hand and thigh sections of human cadavers were analysed in their unprocessed and formalin fixed paraffin processed (FFPP) and subsequently dewaxed forms. In unprocessed sections, KMCA reveals clear differentiation of the stratum corneum, intermediate underlying epithelium and dermal layers for sections from both anatomical sites. The stratum corneum is seen to be relatively rich in lipidic content; the spectrum of the subjacent layers is strongly influenced by the presence of melanin, while that …

Cell Death Pathways In Directly Irradiated Cells And Cells Exposed To Medium From Irradiated Cells, K.K. Jella, Amaya Garcia, Brendan Mcclean, Hugh Byrne, Fiona Lyng

Articles

Purpose: The aim of this study was to compare levels of apoptosis, necrosis, mitotic cell death and senescence after treatment with both direct radiation and irradiated cell conditioned medium. Materials and methods: Human keratinocytes (HaCaT cell line) were irradiated (0.005, 0.05 and 0.5 Gy) using a cobalt 60 teletherapy unit. For bystander experiments, the medium was harvested from donor HaCaT cells one hour after irradiation and transferred to recipient HaCaT cells. Clonogenic assay, apoptosis, necrosis, mitotic cell death, senescence and cell cycle analysis were measured in both directly irradiated cells and bystander cells Results: A reduction in cell survival was …

Raman Spectroscopy In Nanomedicine: Current Status And Future Perspectives, Hugh Byrne, Mark Keating

Articles

Raman spectroscopy is a branch of vibration spectroscopy which is capable of probing the chemical composition of materials. Recent advances in Raman microscopy have added significantly to the range of applications which now extend from medical diagnostics to exploring interfaces between biological organisms and nanomaterials. In this review, Raman is introduced in a general context, highlighting some of the areas in which the technique has found success in the past, as well as some of the potential benefits it offers over other analytical modalities. The subset of Raman techniques which specifically probe the nanoscale, namely Surface Enhanced and Tip Enhanced …

Electric Field Standing Wave Effects In Ft-Ir Transflection Spectra Of Biological Tissue Sections: Simulated Models Of Experimental Variability, Tomasz P. Wrobel, Barbara Wajnchold, Hugh Byrne, Malgorzata Baranska

Articles

The so-called electric field standing wave effect (EFSW) has recently been demonstrated to significantly distort FT-IR spectra acquired in a transflection mode, both experimentally and in simulated models, bringing into question the appropriateness of the technique for sample characterization, particularly in the field of spectroscopy of biological materials. The predicted effects are most notable in the regime where the sample thickness is comparable to the source wavelength. In this work, the model is extended to sample thicknesses more representative of biological tissue sections and to include typical experimental factors which are demonstrated to reduce the predicted effects. These include integration …

A Comparison Of Raman, Ftir And Atr-Ftir Micro Spectroscopy For Imaging Human Skin Tissue Sections., Syed Mehmood Ali, Franck Bonnier, Helen Lambkin, Kathleen Flynn, V Mcdonagh, Claragh Healy, T C. Lee, Fiona Lyng, Hugh Byrne

Articles

Raman and Infrared absorption spectroscopies are compared for the analysis of human hand skin tissue sections. The tissue sections have been formalin fixed and paraffin processed, and subsequently dewaxed. Fourier Transform infrared (FTIR) spectra are preprocessed using the resonant Mie – extended multiplicative scattering algorithm to remove spectral artefacts. FTIR images of resolution 4cm^-1, analysed using K-means cluster analysis, reveal the double layer structure of the dermis and epidermis, but no further layer differentiation is achieved using the higher spatial resolution of the Attenuated Total Reflection imaging or improved spectral resolution of 2cm^-1. At comparable spectral …

Raman Micro Spectroscopy Study Of The Interaction Of Vincristine With A549 Cells Supported By Expression Analysis Of Bcl-2 Protein, Haq Nawaz, Amaya Garcia, Aidan Meade, Fiona Lyng, Hugh Byrne

Articles

Understanding the interaction of anticancer drugs with model cell lines is important to elucidate the mode of action of these drugs as well as to develop cost effective and rapid screening methods. Raman spectroscopy has been demonstrated to be a valuable technique for high throughput, noninvasive analysis. The interaction of vincristine with a human lung adenocarcinoma cell line (A549)was investigated using Raman micro spectroscopy. The results were correlated with parallel measurements from the MTT cytotoxicity assay, which yielded an IC₅₀ value of 0.10 ± 0.03 μM. The Raman spectral data acquired from vincristine treated A549 cells was analysed to …

The Effect Of Genetic Background And Dose On Non-Targeted Effects Of Radiation, Sarah Irons, Virginia Sierra, Deborah Bowler, Kim Chapman, Stefania Militi, Fiona Lyng, Munira Kadhim

Articles

Purpose: This work investigates the hypothesis that genetic background plays a significant role in the signalling mechanisms underlying induction and perpetuation of genomic instability following radiation exposure.

Materials and methods: Bone marrow from two strains of mice (CBA and C57) were exposed to a range of X-ray doses (0, 0.01, 0.1, 1 and 3 Gy). Different cellular signalling endpoints: Apoptosis, cytokine levels and calcium flux, were evaluated at 2 h, 24 h and 7 d post-irradiation to assess immediate and delayed effects.

Results: In CBA (radiosensitive) elevated apoptosis levels were observed at 24 h post X-irradiation, and …

Impaired Clearance And Enhanced Pulmonary Inflammatory/Fibrotic Response To Carbon Nanotubes In Myeloperoxidase-Deficient Mice, Aidan Meade, Anna Shvedova, Alexandr Kapralov, Wei Hong Feng, Elena Kisin, Ashley Murray, Robert Mercer, Claudette St. Croix, Megan Lang, Simon Watkins, Nagarjun Konduru, Brett Allen, Jennifer Conroy, Gregg Kotchey, Bashir Mohamed, Yuri Volkov, Alexander Star, Bengt Fadeel, Valerian Kagan

Articles

Advancement of biomedical applications of carbonaceous nanomaterials is hampered by their biopersistence and proinflammatory action in vivo. Here, we used myeloperoxidase knockout B6.129X1-MPO (MPO k/o) mice and showed that oxidation and clearance of single walled carbon nanotubes (SWCNT) from the lungs of these animals after pharyngeal aspiration was markedly less effective whereas the inflammatory response was more robust than in wild-type C57Bl/6 mice. Our results provide direct evidence for the participation of MPO – one of the key-orchestrators of inflammatory response – in the in vivo pulmonary oxidative biodegradation of SWCNT and suggest new ways to control the biopersistence of …

Assessment Of An Osteoblast-Like Cell Line As A Model For Human Primary Osteoblasts Using Raman Spectroscopy, Lindsay Mcmanus, Franck Bonnier, George Burke, Brian Meenan, Adrian Boyd, Hugh Byrne

Articles

Raman spectroscopy is employed to determine the suitability of the U20S osteoblast-like cell line for use as a model for human primary osteoblasts, with emphasis on the ability of these cell types to replicate their tissue of origin. It was found that both cell types demonstrated early stage mineral deposition that followed significantly different growth patterns. Analysis of the growth pattern and spectral data from primary cells revealed increasing bone quality ratios and a high crystallinity, consistent with previous reports. Conversely the investigation of the U20S osteoblast-like cell line provided evidence of dense multilayered mineralised regions that corresponded more closely …

Quantitative Reagent-Free Detection Of Fibrinogen Levels In Human Blood Plasma Using Raman Spectroscopy, Kelvin Poon, Fiona Lyng, Peter Knief, Orla L. Howe, Aidan Meade, James Curtin, Hugh Byrne, Joseph Vaughan

Articles

Fibrinogen assays are commonly used as part of clinical screening tests to investigate haemorrhagic states, for detection of disseminated intravascular coagulation and as a predictor of a variety of cardiovascular events. The Clauss assay, which measures thrombin clotting time, is the most commonly used method for measuring fibrinogen levels. Nevertheless, inconsistencies are present in inter-manufacturer reagent sources, calibration standards and methodologies. Automated coagulation analysers, which measure changes in optical density during the prothrombin time (PT-Fg), have found use in many hospitals. However, the PT-Fg method is found to give falsely elevated values due to varying choices of calibrants, reagents and …

The Effect Of Participating In Continuing Optometric Education: A Pilot Study, Claire E. Mcdonnell, Martina Crehan

Other

Purpose: To determine whether participation in two different post graduate optometry workshops resulted in a change in practice for the participants, in their subsequent practice.

Methods: 38 optometrists, who had attended a continuing professional development (CPD) workshop on punctal plugs and lacrimal syringing, were surveyed by email and telephone, between four and thirteen months post workshop, to ascertain if they had made a change to their practice. A second group of 32 optometrists, who had attended a continuing education and training (CET) workshop on binocular vision, were surveyed by email, telephone and postal mail between six and nine months post …

Analysis Of Human Skin Tissue By Raman Microspectroscopy: Dealing With The Background, Franck Bonnier, Syed Mehmood Ali, Peter Knief, Helen Lambkin, Kathleen Flynn, Vincent Mcdonagh, Claragh Healy, Thomas Lee, Fiona Lyng, Hugh Byrne

Articles

Raman microspectroscopy is widely used for molecular characterisation of tissue samples. Nevertheless, when working in vitro on tissue sections, the presence of a broad background to the spectra remains problematic and its removal requires advanced methods for pre-processing of the data. To date, research efforts have been primarily devoted to development of techniques of statistical analysis to extract the relevant information contained in the spectra. However, few attempts have been made to understand the origin of the background and to improve the protocols used for the collection of Raman spectra that could lead to the reduction or elimination of the …

The Role Of Colour Duplex Ultrasound In The Surveillance Of Patients Undergoing Endovascular Aneurysm Repair, Cleona Gray

Doctoral

No abstract provided.

Potential Of Vibrational Spectroscopy In The Diagnosis Of Human Tumours., Eoghan O'Faolain

Doctoral

Just fewer than 20,000 people are annually diagnosed with some form of cancer in Ireland and one in three people are likely to contract some form of cancer by age 74. With the number of cases increasing at an annual rate of 2%, the early detection and treatment of cancer is becoming increasingly important. Both IR and Raman spectroscopy offer the potential for real time, quantitative detection of cancer and even precancer. This study investigates the potential of Raman and Fourier transform infrared, both benchtop and synchrotron spectroscopies for the detection of cervical cancer. The tissue was classified and its …

Comparison Of Auto-Adjusting And Fixed Level Continuous Positive Airway Pressure Therapy In Patients With Mild To Moderate Obstructive Sleep Apnoea Hypopnoea Syndrome, Geraldine Nolan

Masters

Obstructive Sleep Apnoea Hypopnoea syndrome (OSAHS) is a potentially serious medical disorder associated with increased morbidity and mortality. It is estimated to affect 4% of males and 2% of females between the ages of forty and sixty. Nasal continuous positive airway pressure (CPAP) is the first choice treatment for this condition and it is extremely effective at controlling OSAHS. However, not all patients can tolerate this therapy, in particular those within the mild to moderate category, and there are also many others who are unable to comply with the minimum usage requirements of at least four hours every night. A …