No description available.

No description available.

No description available.

No description available.

The purpose of this thesis was to investigate the California Consonant Test by manipulating selected variables to determine whether it would be a reliable and valid alternative to the presently used CID W-22 word lists with the sensorineural hearing loss population. This study also looked at the scores obtained on the two discrimination tests and the scores obtained on the Profile Questionnaire for Rating Communicative Performance. In this way, a closer look was taken to determine how much difficulty hearing impaired individuals were reportedly experiencing in understanding speech as compared to their actual performance on the two discrimination tests.The test population consisted of 16 male and 16 female subjects with bilateral symmetrical, sensorineural hearing losses. The CID W-22 Auditory Test and the California Consonant Test (live voice and recorded presentations) were administered to each subject under aided and unaided conditions. At the end of each testing session, each subject was asked to answer the Profile Questionnaire for Rating Communicative Performance in a Home Environment.Pearson's Product-Moment Correlation Coefficient and t-tests for independent measures were calculated to determine if significant correlations existed.It was concluded from this investigation that the California Consonant Test is a more sensitive indicator of the phoneme difficulties experienced by the individuals with &high frequency sensorineural hearing loss than is the' CID W-22 Auditory Test. Although significant correlations were not obtained between the two discrimination tests and the questionnaire, a question by question analysis indicated that all the individuals had at least some difficulties in all situations proposed in this questionnaire. It would therefore seem that the California Consonant Test is a more accurate indicator of the individual's problems in the communicative situation.

The present study investigated early visual information processing of individuals whose Minnesota Mutiphasic Personality Inventory (MMPI-168) profiles indicated schizophrenic tendencies in the absence of an obvious thought disorder. These schizotypic individuals were identified by the 2-7-8 M PI code type and were compared on a visual backward masking task with three other groups: an "Inflation-free" group, an "Other-inflations" group, and a group with an "8-9" MMPI code. The 2-7-8 and the 8-9 groups had significantly fewer correct identifications of target stimuli than either the Inflation-free group or the Other-inflations group. The 2-7-8 group had significantly higher Critical Stimulus Durations (CSD) than either the Inflation-free group or the 8-9 group. These results suggest that both the 2-7-8 group and the 8-9 group are more vulnerable to the effects of the masking stimulus. Schizophrenics have demonstrated similar susceptibility to masking stimuli. It is suggested that both the 2-7-8 and the 8-9 M I profile code may be an index of vulnerability to schizophrenia.

Obesity-related glomerulopathy (ORG) is an emerging epidemic for which an established model, diagnostic guidelines, and dietary treatments are absent. Oxylipins influence inflammation and hemodynamics, yet the renal oxylipin profile or the influence of dietary linoleic acid (LA) and alpha-linolenic acid (ALA) on their formation has yet to be examined. Therefore, obese-prone rats were provided high fat lard/soy diets to induce obesity and subsequently divided among 7 diets with varying LA and ALA levels. The diet-induced obese experimental model developed characteristics of ORG; morphology and histology revealed glomerulomegaly as an early diagnostic marker as it was the first pathological change and indicated further renal damage. Liquid chromatography-tandem mass spectrometry detected 30 oxylipins. Higher dietary ALA resulted in greater n-3 oxylipin levels and resulted in reduced progression of glomerulomegaly and glomerular damage. To conclude, ORG may be diagnosed earlier with glomerulomegaly and treated with dietary oils rich in ALA which alter the oxylipin profile.

Transmissible spongiform encephalopathies (TSEs), or prion diseases, are a group of invariably fatal neurodegenerative diseases of both humans and animals, thought to be caused by the abnormally folded prion protein PrPSc. Prion disease research continues to be faced by a number of difficult challenges. First, the unequivocal diagnosis of most prion diseases currently requires the post-mortem collection of central nervous system tissue, either for histological examination or Western blot analysis; second, a viable treatment for clinical stage disease has not yet been identified; third, the exact details of disease pathogenesis have not been elucidated; and fourth, the normal function of PrPC is not definitively known. The primary objective of the studies presented here was to diagnose prion disease in live animals, using Magnetic Resonance Imaging (MRI). Increases in T2 relaxation time and apparent diffusion coefficient (ADC) were observed very early following the infection of Syrian golden hamsters with the 263K strain of scrapie. These changes were evident well before the appearance of either clinical symptoms or the typical histological changes characteristic of prion disease, suggesting that they are the result of the progressive accumulation of fluid, and that this may constitute a novel early marker of prion disease pathogenesis. Following the establishment of this model system, a secondary objective was composed: to test the viability of a potential treatment (pentosan polysulphate) using a number of different treatment regimens. It was determined that pentosan polysulphate (PPS) was ineffective as a treatment unless it was administered intra-cerebrally very early in infection, although it was shown to slow the appearance of the histological hallmarks of prion disease. In response to the results of these studies, a potential model was proposed, relating PrP, aquaporin-4 (AQP4) regulation, and oedema. Although speculative, this model may have implications for both normal PrPC function and disease pathogenesis.

No description available.

The short-lived PET radionuclide (^134)La(t(_1/2)=6.7 minutes) is well suited to the repeated evaluation of blood perfusion, thus providing a method of following changes in tumour behaviour, in response to therapy. Ligands, both acyclic and macrocyclic, have been synthesised, and the complexes formed with (^134)La(^3+) evaluated in vitro and in vivo. Other lanthanide complexes have also been evaluated for potential use in magnetic resonance imaging and photoimmunoassay studies. A preliminary crystal structure determination of a lanthanum tetrabenzylphosphinate complex reveals the presence of one water molecule in the inner co-ordination sphere. The development of monoclonal antibodies with a specificity for the surface features of tumour cells presents a method for the localisation of a radionuclide at the tumour. Copper-64 (t(_1/2)=12.7 hours) uniquely combines the decay properties required for imaging and therapy. Ligands have been developed for derivatising antibody molecules with radioactive copper, whilst retaining specificity for the target antigen. Three modified proteins have been evaluated in vivo, and show a high tumour uptake compared with blood, but modest uptake compared with the liver, suggestive of some degree of protein denaturation during labelling. A more subtle approach has been developed, exploiting the affinity of biotin for avidin. Higher selectivity at much shorter post-administration time is potentially attainable by the use of a multi-step procedure. A copper binding ligand incorporating biotin has been synthesised. The (^64)Cu complex of the conjugate shows specificity for the protein avidin both in vitro and in vivo. The prognosis of patients with hepatoma or liver metastases is poor. A lipophilic copper complex has been synthesised and retention in the liver demonstrated in vivo. Measurements with three cell lines in vitro suggest that the complex is more readily taken up by tumour cells (and cells from metastases) compared to normal cells.