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D Weller

Publications and source records attributed to D Weller.

At least 55 records · Page 3Linked to original sources
PubMed1994

Screening for colorectal cancer. Knowledge, attitudes and practices of South Australian GPs.

OBJECTIVE: To examine knowledge, attitudes and practices of South Australian general practitioners (GPs) in relation to screening for colorectal cancer. DESIGN: A descriptive study in which data were collected by means of postal questionnaires. MAIN OUTCOME MEASURES: Use of screening tests for colorectal cancer, knowledge in relation to colorectal cancer prevention, opinions on organisation and delivery of colorectal cancer screening. RESULTS: The response rate to the survey was 66.3%. GPs showed considerable variability in screening practices, particularly for individuals who are at no increased risk of colorectal cancer. Mass screening with the faecal occult blood test (FOBT), particularly if it is centrally coordinated, was not widely endorsed, in contrast with strategies which provide a central role for the GP. On the whole, GPs preferred patient-initiated, rather than doctor-initiated, screening. We found a number of knowledge deficits in relation to FOBT screening; many GPs felt they had inadequate training in this area. CONCLUSION: Clear and consistent guidelines for colorectal cancer screening are required. Medical education about colorectal cancer should also be addressed.

Colorectal Neoplasms↗
PubMed1994

Screening for colorectal cancer using an immunochemical test for faecal occult blood: results of the first 2 years of a South Australian programme.

This paper reports an evaluation of the first 2 years of a South Australian screening programme for colorectal cancer which was established in 1988 by the Institute of Medical and Veterinary Science. The programme uses an immunochemical test for faecal occult blood. Based on 1 year of follow-up, over the period of this analysis there were 24 cancers and 99 adenomas detected in 6208 participants, and the estimated sensitivity and specificity of the test (for colorectal cancer) were 82.8 and 95.9%, respectively. In many cases the test was used to detect recurrence of disease in individuals with a previous diagnosis of colorectal cancer. The estimated predictive value of a positive test for colorectal cancer in this population was 7.5%. Results suggest that participants belonged to higher-than-average socio-economic groups and were more likely than the general population to have a family history of colorectal cancer. Almost one-third had suffered from bowel symptoms in the 6 months before taking the test. These unique characteristics of participants, which limit the generalizability of results to the wider population, may result from the programme's reliance on self-recruitment methods. Consistent evidence for improvements in mortality in populations screened for colorectal cancer is still required before a recommendation for widespread screening in Australia can be made.

Adult↗
PubMed1992

Stacking interactions of ApA analogues with modified backbones.

CD spectra have been measured as a function of temperature for a number of ApA analogues with modified backbones. Oligonucleotides with these modified backbones are being used as antisense agents having potential as viral therapeutics. Results of these studies show that when a carbonyl is substituted for the phosphate to produce an uncharged backbone, the analogues that have either sugar or morpholino substitution do not stack. In contrast, when a morpholino group is substituted for the sugar and the phosphate is modified so as to be uncharged, there is strong base stacking. Stacking interactions in the phosphorus-linked morpholino analogues are at least as strong as those found in d(ApA). The stacking interactions in ApA are weak by comparison. Singular value decomposition demonstrates that the stacking is two state, and Taylor series decomposition yields a coefficient that measures base stacking interactions. The van't Hoff equation is applied to the base stacking coefficient from the Taylor series fitting to give thermodynamic parameters.

Circular Dichroism↗
PubMed1991

Antibacterial activity and inhibition of protein synthesis in Escherichia coli by antisense DNA analogs.

Protein synthesis, which takes place within ribosomes, is essential for the survival of any living organism. Ribosomes are composed of both proteins and RNA. Specific interaction between the 3' end CCUCC sequence of prokaryotic 16S rRNA and a partially complementary sequence preceding the initiating codon of mRNA is believed to be a prerequisite for initiation of protein synthesis. Here we report the use of short (three to six nucleotides) synthetic DNA analogs complementary to this sequence to block protein synthesis in vitro and in vivo in Escherichia coli. In the DNA analogs the normal phosphodiester bond in the antisense DNA was replaced by methylcarbamate internucleoside linkages to enhance transport across plasma membranes. Of the analogs tested, those with the sequence AGG and GGA inhibit protein synthesis and colony formation by E. coli strains lacking an outer cell wall. Polyethylene glycol 1000 (PEG 1000) was attached to the 5' end of some of the test methylcarbamate DNAs to enhance solubility. Analogs of AGG and GGAG with PEG 1000 attached inhibited colony formation in normal E. coli. These analogs may be useful food additives to control bacterial spoilage and biomedically as antibiotics.

3T3 Cells↗
PubMed1990

Colorectal cancer: implications of mass screening for public health.

The faecal occult blood test (FOBT) for colorectal cancer has a place in clinical practice in case finding, and, perhaps, in screening high-risk groups, but is it a worthwhile screening test when applied to the general population? This question is important and topical: there is increasing interest in Australia in screening by FOBT, but such a programme would be neither free of risk, nor inexpensive. We argue that there is not yet satisfactory evidence that screening by FOBT reduces mortality from colorectal cancer. There is no quicker way of learning whether FOBT saves lives than to wait for the results of the major overseas trials, the first of which should become available in the next three to five years. Until this evidence becomes available, Australia should not proceed with mass screening for colorectal cancer by FOBT. Sporadic and haphazard screening should be discouraged. What we can, and should, do now is find out more about the attitudes and behaviour of consumers and providers of screening by FOBT, the infrastructure that would be required to promote and sustain an effective mass screening programme, the total costs of colorectal cancer screening, and the performance in representative populations of new screening technologies.

Australia↗