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R E Duncan

Publications and source records attributed to R E Duncan.

At least 19 recordsLinked to original sources
PubMed2006

Predictive genetic testing in young people for adult-onset conditions: where is the empirical evidence?

Predictive genetic testing in young people for severe, adult-onset conditions is advised against in current guidelines. Despite this, there has been considerable debate regarding the issue. Some perceive such testing as too potentially harmful to allow. Others perceive it as an opportunity for the promotion of benefit, an opportunity even for the prevention of harm. The only way to resolve this theoretical debate is to collect empirical data related to the effects of such testing when it occurs. However, more than 15 years after the debate began, there is virtually no such empirical evidence available. The reasons for this lack of evidence appear to relate to the rarity of such testing, which when it occurs is not studied systematically. Additionally, clinicians performing such tests may feel vulnerable in sharing the outcomes, given that such testing is contrary to current recommendations. We propose a way forward that entails the provision of tests to mature minors, where clinicians deem this appropriate. These tests should be performed as part of an international research collaboration, facilitated by one leading group.

Adolescent↗
PubMed2005

Ethical considerations in presymptomatic testing for variant CJD.

Variant Creutzfeldt-Jakob disease (vCJD) is a fatal, transmissible, neurodegenerative disorder for which there is currently no effective treatment. vCJD arose from the zoonotic spread of bovine spongiform encephalopathy. There is now compelling evidence for human to human transmission through blood transfusions from presymptomatic carriers and experts are warning that the real epidemic may be yet to come. Imperatives exist for the development of reliable, non-invasive presymptomatic diagnostic tests. Research into such tests is well advanced. In this article the ethical implications of the availability of these tests are elaborated and comparisons drawn with predictive genetic testing for Huntington's disease and screening for HIV. Paramount to considerations is the issue of whom to test, weighing up respect for personal autonomy against obligations to benefit and protect society. A paradigm is proposed similar to that used for HIV screening but with unique features: compulsory testing of all blood/organ donors and individuals undergoing surgery or invasive procedures who have a significant risk of disease transmission.

Animals↗
PubMed2004

Predictive genetic testing in young people: when is it appropriate?

Predictive genetic testing is currently offered to adults for a range of conditions, even when there is no possibility of prophylaxis or treatment. However, similar testing in children and adolescents is advised against in international guidelines. Despite this, several authors have argued against the existing guidelines. Given the lack of empirical evidence, it is important that clinicians are aware not only of the guidelines, but also of the arguments in favour of such testing.

Adolescent↗
PubMed2003

Putting the 'informed' into 'consent': a matter of plain language.

Health professionals frequently write at the same level for lay readers as they write for peers. In relation to health research and ethical requirements to provide written explanation of studies, this can complicate the notion of informed consent. Plain language information statements need to be clearly understood by research subjects if the ethics process for research approval is to fulfil its objective. Many delays in gaining ethics approval for child-related research are caused by substandard plain language statements (PLS). We describe specific issues for information statements for research with children, young people and their parents/guardians, particularly in consideration of the literacy capabilities of the general population. We highlight the usefulness of everyday language when explaining research and science in writing to families, and present some guidelines for writing PLS that have emerged from the introduction of a plain language service by an Ethics in Human Research Committee.

Child↗
PubMed1995

Cloning and characterization of two cDNA clones encoding seed-specific antimicrobial peptides from Mirabilis jalapa L.

We have isolated and characterized two cDNA clones (designated MJ1 and MJ2) encoding the two Mirabilis jalapa antimicrobial peptides (Mj-AMP1 and Mj-AMP2, respectively), which were previously purified from seeds of this plant species (Cammue et al. (1992), J Biol Chem 267: 2228-2233). In both cases, the deduced amino acid sequences reveal the presence of a putative signal sequence preceding the mature peptide, indicating that the Mj-AMPs are expressed as preproteins. The Mj-AMP1- and Mj-AMP2-encoding genes are interrupted in their coding sequences by a single intron (380 bp and 900 bp for Mj-AMP1 and Mj-AMP2 genes, respectively). Southern blot analysis indicates that the Mj-AMP-encoding genes belong to a gene family of low complexity. Northern blot analysis suggests seed-specific expression of Mj-AMPs since transcripts of the expected size could only be detected in near-mature and in mature seeds of M. jalapa.

Amino Acid Sequence↗
PubMed1981

Esterification of terminal phosphate groups in nucleic acids with sorbitol and its application to the isolation of terminal polynucleotide fragments.

The exposure of mono- and polynucleotides to 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide and high concentrations of sorbitol results in the esterification of their monosubstituted phosphate groups. The presence of the sorbitol moiety permits these derivatives to bind strongly at pH 8.7 to columns of chromatographic supports containing the dihydroxyboryl group and to be subsequently released by elution with buffers at pH 5.5. The procedure constitutes a method for the isolation of polynucleotide fragments arising from the terminals of nucleic acids. A new method for the preparation of the chromatographic supports involves the synthesis of the 1,3-propanediol cyclic ester of m-[[3-(N-succinimidoxycarbonyl)propanoyl]amino]benzeneboronic acid and its condensation with aminoethylcellulose or amino-ethylpolyacrylamide. The reagent is readily prepared by reaction of N-[m-(dihydroxyboryl)phenyl)]succinamic acid with 1,3-propanediol to protect the boronate moiety followed by esterification with N-hydroxysuccinimide in the presence of dicyclohexylcarbodiimide.

Animals↗
PubMed1977

Natural history and treatment of renal vein thrombosis in children.

The general features and problems of renal vein thrombosis in children are first discussed. The records of 11 children with this condition, 7 ill neonates and 4 older children with burns, are then reviewed, indicating the clinical course of the disease, how they were treated, the results, and pathological findings. From this study, the natural history is assembled and a protocol for treatment is proposed. Supportive therapy is necessary in all cases to correct dehydration and sepsis. Many children will develop a consumptive coagulopathy. Others will develop pulmonary emboli associated with thrombosis of the inferior vena cava. Anticoagulation should be achieved for these two conditions. Nonvisualization of affected renal units upon initial urographic examination virtually assures an atrophic, functionless kidney later. Nephrectomy will be required because of hypertension, persistent infection, and scarring. Thrombectomy may be attempted when bilateral nonvisualization on urography is associated with a positive venacavogram.

Anticoagulants↗
PubMed1977

Radiation-induced bladder tumors.

A recent 25-year experience with patients treated for carcinoma of the uterine cervix who subsequently had bladder tumors is presented. Of the 3,091 patients treated 2,674 had received radiotherapy and 8 suffered vesical malignancies of varied histopathological type 6 months to 20 years after irradiation. This incidence rate is 299.9 per 100,000, which is 57.6 times that of the general female population. Benign radiation reactions of the bladder and the possible etiology of radiation-induced bladder cancers are discussed.

Adult↗
PubMed1977

Diagnosis of primary retroperitoneal tumors.

An analysis of 27 cases of primary retroperitoneal tumors and a review of the literature are presented. Techniques available for the diagnosis of these neoplasms are discussed. Sarcoma is the most common histopathologic type. A painful abdominal mass is the characteristic presentation. Echography, angiography and carbon dioxide pneumography may provide specific diagnostic information but further histopathologic correlation is needed. Angiography should guide the surgical approach routinely. Surgical excision is the treatment of choice for all tumors except for the lymphomas, which are radiosensitive. Radiotherapy has liberal application in the treatment of other histopathologic types.

Adult↗
PubMed1975

Squamous cell carcinoma of the ureterovesical junction after renal transplantation.

A case of squamous cell carcinoma of the bladder occurring at the ureterovesical junction in a renal transplant recipient is presented. References are made to ureteral obstruction in transplanted kidneys, the broader field of squamous cell carcinoma of the bladder in non-transplanted patients and the relationship of malignancy to transplantation. We anticipate that an ever increasing number of these unusual cases will be forthcoming in the urological literature as renal transplantation develops.

Carcinoma, Squamous Cell↗