/library/oar/handle/123456789/40247 2026-06-19T13:33:32Z /library/oar/handle/123456789/40354 Title: A study of the cost-effectiveness of colorectal cancer screening in the Maltese Islands. Abstract: This study purports to investigate the cost-effectiveness of a possible national colorectal cancer screening programme, the general public's awareness of the condition, its prevalence and risks, the possible rate of compliance and the reasons for non-compliance if ever such a programme were to take off. Screening would be offered to all those aged 50 to 69, comprising 20.9% or 80,000 of the Maltese population. The initial screening test would be faecal occult blood testing every 2 years. The programme, administered by a newly set up screening centre would invite 10,000 every quarter. The compliance rate would be in the region of 50%. The invitation and test kit would be sent by post some time before the beginning of each quarter. Those with a positive initial screen (2%) would be recalled for assessment, resulting in 100 investigations every quarter. Deviation in the compliance rate would affect resources and costs. Colonoscopy and possible double-contrast barium enema (DCBE) would be used for further investigation - both procedures being carried out by highly skilled professionals to significantly reduce possible mortality from colonoscopy which has been quoted at 0.02%. All professionals involved would be co-ordinated by a programme manager and quality assurance would form an integral part of the whole programme. The total cost of the programme would reach LM230, 120 per year. Given an overall uptake rate of 50% and a test sensitivity of 60%, 30% of all cancers in this age bracket (50-69 years) would be detected. These add up to 50 cancer cases and 230 new cases of adenomas. Added life expectancy for those with cancer would range between 2 and 1.35 years; so the cost per life year gained would fluctuate between LM2,301 and LM3,400. This is a small but significant benefit. Description: M.SC. PUBLIC HEALTH 2001-01-01T00:00:00Z /library/oar/handle/123456789/32266 Title: The role of the mesolimbic dopamine system in interferon-α mediated anhedonia Abstract: SAMMUT, S. The role of the mesolimbic dopamine system in Interferon-a mediated anhedonia Changes in sucrose intake were used as a measure of anhedonia. Non-drug manipulations confirmed that the differences observed in the sucrose concentration-intake curve between the single-bottle and three-bottle were not due to aversion or satiety but more likely attributable to an effort to regulate reward to an optimal level. In the single-bottle test increasing hours of deprivation prior to sucrose tests, nonspecifically altered sucrose intake, while increasing the response-force requirement to access the sucrose solutions decreased the consumption of the 1 % solution and increased the intake of the 32% solution, effectively shifting the bell-shaped response reward curve to the right. This effect was attributed to the motivational drive associated with the perceived reward value of the sucrose solution on offer. Sucrose intake is subject to modulation by several neurotransmitters including DAergic as evident by the effects of raclopride (RAC), a D2/D3/D4 receptor antagonist, glutamatergic (MK-801, non-competitive NMDA receptor antagonist) and GABAergic (muscimol and b acI of en , GABAA and GABAB receptor agonists respectively) systems which showed a similar intake pattern to those of increased response force requirement (i.e. decreased consumption at the 1 % sucrose solution and increased consumption at the 32% solution). Administration of chlordiazepoxide (CDP, a benzodiazepine anxiolytic) however, produced a non-specific increase at all concentrations of sucrose. These results indicate a close interaction between DA, GABA and glutamate in sucrose reward and anhedonia. rHIFN-α is a cytokine used in the treatment of various viral illnesses. A major limiting factor in the therapy is depression. Acute administration of rHIFN-α decreased sucrose intake in a three-bottle test at all concentrations of sucrose, although the effect was greater at 1 % solution. Chronic administration of rHIFN-α decreased sucrose intake at the 1 % and increased that at the 32%. The increase in consumption of the 32% solution was reversed by the chronic administration of a tricyclic and selective serotonin reuptake inhibitor antidepressant. rHIFN-α however failed to alter locomotor activity or amphetamine (AMP)-induced sensitisation. Using in vitro voltammetry in brain slices, it was shown that peripheral pretreatment with AMP led to increased levels of DA in the nucleus accumbens (NAcb) core relative to the rats that had been treated with vehicle. rHlFN- α, reduced evoked DA release in the NAcb core at all frequencies of stimulation. The administration of anti-human lFN-cx, antibody (mHlFNAb) reversed the decrease in sucrose intake at the 32% solution produced by the acute administration of rHlFN-cx,. This strongly suggests that the behavioural effects produced by lFN- α, may be related to these central dopaminergic changes. These findings are discussed in relation to a behavioural model for rHINF-α,-induced depression and relative to furthering our understanding into the possible mechanisms through which rHIFN-α, may produce depression in patients and possible therapeutic strategies to alleviate such. Description: PH.D. 2001-01-01T00:00:00Z