Lynch Syndrome is caused by mutations in the DNA mismatch repair (MMR) genes; MLH1, MSH2, MSH6 and PMS2. An accurate estimation of cancer risk for MMR mutation carriers is essential for counselling and screening. United Kingdom (UK) specific cancer risks for MMR mutation carriers and cumulative colorectal cancer risks by decade have not been described to date. Using data from 121 Lynch Syndrome families, the cumulative lifetime risks of Lynch Syndrome spectrum cancers in mutation carriers were calculated, correcting for ascertainment bias. This data provides reassurance that current UK screening guidelines are appropriate. For colorectal cancer, tables of risk by decade were compiled for carriers of the different gene mutations. This novel data represents a useful counselling tool. Despite an increased cancer risk, individuals with Lynch Syndrome lack clear phenotypic characteristics. Mutation carrier identification is desirable as screening reduces mortality. After counselling and assessment of family history against clinical criteria, molecular diagnosis of tumour tissue is performed. Immunohistochemistry (IHe) of the MMR proteins has great potential as a method of identifying the most likely mutation and guiding mutation analyse. However IHC of the MMR proteins is not yet well established and problems have been reported with staining and slide interpretation. IHC slide assessment methods in the reported literature have been qualitative. This thesis describes the development and validation of a robust, semiquantitative scoring technique to be used in the assessment of IHC stained tumour sections from patients with possible Lynch Syndrome. Colorectal tumour sections from 51 MMR mutation carriers were stained with 3,3' Diaminobenzidine (DAB) using antibodies against the MMR proteins. Slide assessment was semiquantified using a 0-12 scale, and was found to be highly sensitive and specific for the identification of mutation carriers. It was found however, that protein expression may occur in the context of known pathogenic mutations, a potential pitfall in the screening process. Two quantitative techniques of slide assessment that could potentially obviate the need for human operator slide analysis were explored. Semiconductor quantum dots (QOs) are quantifiable fluorescent labels that can be used for multiplex staining. Quantitative QO IHC was compared to quantitative DAB IHC. Both are novel methodologies. Tumour sections from 36 mutation carriers were stained using each method, and multispectral analysis of the slides was performed. Quantitative analysis of the DAB stained slides was less sensitive than semi-quantitative analysis in this study, but was sufficiently sensitive to be used as a pre-screen in Lynch Syndrome. However despite the potential advantages of quantitative QD staining, it was less sensitive and specific than quantitative DAB IHC. The development of automated DAB IHC staining and quantitative multispectral slide analysis may enable future high throughput IHC for MMR mutation carrier identification. Around 15% of sporadic colorectal cancers develop along the MSI pathway due epigenetic MLH1 inactivation. The evidence suggests that patients with such tumours do not benefit from 5-Fluorouracil based chemotherapy. The cost effectiveness of identifying patients with such tumours was explored. Potential chemotherapeutic savings are substantial, supporting the introduction of this biomarker into clinical practice. The improved diagnostic accuracy of semi-quantitative IHC slide assessment and the potential for automation of quantitative IHC slide assessment would facilitate the introduction of this service.

No description available.

As new materials are discovered, their potential and applications are investigated widely across the various scientific disciplines for general or highly specialized applications. While new nanomaterials such as carbon nanotubes have received the greatest interest for electronics, optics, and structural composites, their applications have also been explored for biological applications such as sensing, selective cell destruction, cellular growth scaffolds, and intracellular delivery of bioactive cargos. Carbon nanotubes are unique materials particularly suited for these applications as they possess characteristic optical and electronic properties in conjunction with large aspect ratios and massive surface areas. The work of this thesis explores the use of carbon nanotubes for cellular growth scaffolds in Chapters 3, tailoring the various properties of these scaffolds in Chapter 4, and their cellular internalization and intracellular locations in Chapter 5. The aim of Chapters 3 and 4 are to create a surface that mimics a cell's natural environment by varying characteristics such as roughness, pore size distribution, wettability, and chemical functionalization of the carbon nanotubes surface. Such variations can have beneficial, detrimental or abnormal effects on the tested cell line as a cell's natural environment within the body consists of a three dimensional mesh of extracellular matrix proteins which is not at all replicated by the commonly used polystyrene tissue culture flask. Carbon nanotubes possess diameters ranging from 0.7 to several nanometers and lengths that can range up to several microns thereby allowing certain types of CNTs to scale with these extracellular matrix proteins and thus impart a nanoscale textured topology that more closely resembles a cell's in vivo environment. Additionally, the replacement of extracted extracellular matrix proteins for coating cellular growth surfaces with synthetic carbon nanotubes eliminates any risk of pathogen contamination and batch-to-batch variability of biological specimens. Fundamental understanding of the interactions between carbon nanotube surfaces and adhered cell cultures will provide a foundation for carbon nanotube applications in 3- dimensional cellular growth scaffolds and tissue implantation devices. Chapter 5 explores the interactions between designed peptides with slight variations in their amino acid sequences and the consequential effects of these peptide interactions with carbon nanotubes for cellular internalization and intracellular location. The efficacy of pharmaceutical drugs and the cellular responses to biomacromolecules depends heavily upon their abilities to transverse the cellular plasma membranes, and exploring the interactions with designed biomolecules such as synthetic peptides provides simple methods for increasing the cellular internalization of carbon nanotubes and altering the intracellular delivery location. The results and methods investigated within these chapters can then be easily applied to other carbon nanotube transporter schemes.,

Despite an elaborate int;icacy the brain can, to some degree, be understood in terms of surprisingly simple features. This thesis considers the brain from one such perspectivethat of oscillatory dynamics-in order to study, compare and fina.lly model the awake and anresthetized states of consciousness. Anresthesia provides a comparatively simple state in which to study the brain and understanding how this state differs from the awake state could help improve the safety of many modern surgical procedures which require general anresthetics. The importance of including glia-an often overlooked group of brain cells-is also argued, leading to a novel neuron-glia brain model. This thesis is comprised of four parts: a literature-based review of brain dynamics and anresthesia; analysis of human electroencephalograms (EEGs); a.n oscillation-based brain model; and a unifying discussion of this work. Part one begins with the cellular (i.e. neuronal and glial) dynamics of the brain, thus describing the underlying oscillatory nature of brain dynamics. This is followed by a detailed overview of macroscopic "brain-waves", their hypothetical functional correlates and likely mechanisms of generation. This discussion proceeds to an overview of the mechanisms of general anresthesia and their effects upon brain dynamics. Part two of this thesis begins with a description of the relevant mathematical concepts and tools-a necessary precursor to the technical analysis of EEG data which will follow. Conclusions drawn from this analysis compliment those presented in the preceding sections and provide a foundation upon which the model can be built. Part three initially overviews various brain-models and then utilizes preceding sections in order to formulate an oscillation-based brain model. The resulting model hence depends upon a multi-scale understanding of brain dynamics and replicates some of the conclusions drawn from my own analysis while also demonstrating.

No description available.

A tissue microarray method yielded staining of good quality and is feasible for morphological and immunohistochemical studies in cervical adenocarcinoma. Analysis of two TMA cores achieved 100% representation for morphological studies and greater then 97% representation for immunohistochemical studies. Tissue array sections were immunostained with 8 antibodies, carcinoembryonic antigen (CEA). Cytokeratin7 (CK7), Cytokeratin20 (CK20), oestrogen receptor (ER), progesterone receptor (PgR), phosphatase and tensin homolog deleted on chromosome ten (PTEN), MIB-1 proliferation marker, and p53 suppressor gene utilizing the power vision technique for ER only and Envision technique for all other antibodies. Our findings support that all of these 8 antibodies are of potential biomarkers of a panel of antibodies for diagnosis of cervical adenocarcinomas. HPV DNA was extracted from paraffin-embedded, formalin-fixed tissues of 161 specimens of 139 patients with excluding 22 patients with the second samples and 16 normal cervical tissues. HPV DNA was detected by PCR test using type specific primers from the <i>E6</i> gene and E7 gene of HPV type 16 and HPV type 18. HPV DNA was identified in 87 cases (62.6%) in which, HPV16 was positive for 65 (47%) patients and HPV18 was positive for 41 (29%) patients. Genotyping by RFLP and PCR revealed that, HPV type 16 was the most frequent type of infection comprising 46 cases (33%), followed by HPV type 18 in 22 cases (16%), and both HPV type 16 and HPV type 18 in 19 cases (14%). HPV typing in all cases of 16 normal cervical biopsies revealed negative with both HPV type 16 and HPV type 18. Our findings support that HPV 16, along with HPV 18, may play a possible role in the pathogenesis of adenocarcinoma of the uterine cervix.

No description available.

No description available.

Excessive fat deposition in the form of obesity is now a major health problem worldwide leading to an increased risk of a number of diseases, including type II diabetes, coronary heart disease and cancer. Adipose tissue was originally thought to be used by the body solely as an energy store. In recent years, increases in the prevalence of obesity and ongoing research, has shown that lipid storage is not the only function of white fat. The disc overy of leptin, which was followed by the identification of other protein factors, termed 'adipokines', secreted by white adipose tissue 0VAT), indicated that WAT is major endocrine organ.

No description available.