Evaluation of catheter-induced tribological damage to porcine aorta using infra-red spectroscopy

© 2016 Elsevier Ltd Studies were carried out to assess the potential of attenuated total internal reflection Fourier transform infrared (ATR)-FTIR spectroscopy as a tool for evaluating mechanical-tribological damage to the blood vessel wall occurring during simulated endovascular catheterization on fresh ex-vivo porcine aortic tissue. It is envisaged that this method could be used in laboratory tests to quantitatively compare catheters or catheterization approaches with regard to their effect on damage to the aorta wall. Tribological damage was induced on the tissue. Obvious changes were visible in the FTIR spectra as well as the friction coefficient as a function of increasing damage. In particular, the spectral changes due to damage to the outermost layer of the tissue were significant, provided appropriate sample conditioning was performed. These changes, which correlated with a reduction in friction coefficient, can be attributed to the removal of successive layers of tissue as a result of a wear process. In conclusion, FTIR spectroscopy was found to be a reliable and effective measurement technique for quantifying catheter-induced tissue damage, allowing very repeatable spectra to be obtained from the tissue up to 36 h after excision with no major spectral changes observed during this time frame due to tissue age

Correlation of p16INK4A Expression and HPV Copy Number with Cellular FTIR Spectroscopic Signatures of Cervical Cancer Cells

Cervical cancer, a potentially preventable disease, has its main aetiology in infection by high risk human papillomavirus (HR-HPV). Approaches to improving cervical cancer screening and diagnostic methodologies include molecular biological analysis, targeting of biomarker proteins, but also exploration and implementation of new techniques such as vibrational spectroscopy. This study correlates the biomarker protein p16INK4A expression levels dependent on HPV copy number with the infrared absorption spectral signatures of the cervical cancer cell lines, HPV negative C33A, HPV-16 positive SiHa and CaSki and HPV-18 positive HeLa. Confocal fluorescence microscopy demonstrated that p16INK4A is expressed in all investigated cell lines in both nuclear and cytoplasmic regions, although predominantly in the cytoplasm. Flow cytometry was used to quantify the p16INK4A expression levels and demonstrated a correlation, albeit nonlinear, between the reported number of integrated HPV copies and p16INK4A expression levels. CaSki cells were found to have the highest level of expression, HeLa intermediate levels, and SiHa and C33A the lowest levels. FTIR spectra revealed differences in nucleic acid, lipid and protein signatures between the cell lines with varying HPV copy number. Peak intensities exhibited increasing tendency in nucleic acid levels and decreasing tendency in lipid levels with increasing HPV copy number, and although they were found to be nonlinearly correlated with the HPV copy number, their dependence on p16INK4A levels was found to be close to linear. Principal Component Analysis (PCA) of the Infrared absorption spectra revealed differences between nuclear and cytoplasmic spectroscopic signatures for all cell lines, and furthermore clearly differentiated the groups of spectra representing each cell line. Finally, Partial Least Squares (PLS) analysis was employed to construct a model which can predict the p16INK4A expression level based on a spectral fingerprint of a cell line, demonstrating the diagnostic potential of spectroscopic techniques

EFFECTS OF INSECT GROWTH REGULATORS (IGRs) ON THE EMBRYO AND LARVAE OF CHIRONOMUS COSTATUS AND AEDES ALBOPICTUS

Ph.DDOCTOR OF PHILOSOPH

The paradox of fiction: the rationality of our emotional responses to works of fiction

This paper seeks to explore the paradox of fiction, or more precisely, the paradox of why we are able to genuinely emotionally respond to characters, objects and situations in works of fiction. I argue that the paradox can be resolved by refining the second premise, asserting that we can have genuine, rational emotional responses to fictional characters/objects/situations even if we do not believe that they exist in real life, as long as they could potentially exist in real life or our emotional responses themselves are aligned with aesthetic conventions and conveyed appropriately. With a brief review of existing literature on this topic, I provide a justification for this refinement of the second premise by looking at our cognitive abilities of empathy and mental associations, as well as the notion of aesthetic conventions in our engagement and appreciation of works of art/fiction.Bachelor of Arts in Philosoph

Infrared spectral features of exfoliated cervical cells, cervical adenocarcinoma tissue, and an adenocarcinoma cell line (SiSo)

10.1006/gyno.2002.6602Gynecologic Oncology851170-174GYNO

Letter to the editor (multiple letters)

10.1016/S0090-8258(03)00358-5Gynecologic Oncology911275-277GYNO

Segregation of ovarian cancer stage exploiting spectral biomarkers derived from blood plasma or serum analysis:ATR-FTIR spectroscopy coupled with variable selection methods

Ovarian cancer is a solid tumor and a leading cause of mortality. Diagnostic tools for the detection of early stage (stage I) ovarian cancer are urgently needed. For this purpose, attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) coupled with variable selection methods, successive projection algorithm or genetic algorithm (GA) combined with linear discriminant analysis (LDA), were employed to identify spectral biomarkers in blood plasma or serum samples for accurate diagnosis of different stages of ovarian cancer, histological type and segregation based on age. Three spectral datasets (stage I vs. stage II?IV; serous vs. non-serous carcinoma; and, ≤60 years vs. >60 years) were processed: sensitivity and specificity required for real-world diagnosis of ovarian cancer was achieved. Toward segregating stage I vs. stage II?IV, sensitivity and specificity (plasma blood) of 100% was achieved using a GA-LDA model with 33 wavenumbers. For serous vs. non-serous category (plasma blood), the sensitivity and specificity levels, using 29 wavenumbers by GA-LDA, were remarkable (up to 94%). For ≤60 years and >60 years categories (plasma blood), the sensitivity and specificity, using 42 wavenumbers by GA-LDA, gave complete accuracy (100%). For serum samples, sensitivity and specificity results gave relatively high accuracy (up to 91.6% stage I vs. stage II?IV; up to 93.0% serous vs. non-serous; and, up to 96.0% ≤60 years vs. >60 years) using several wavenumbers. These findings justify a prospective population-based assessment of biomarkers signatures using ATR-FTIR spectroscopy as a screening tool for stage of ovarian cancer