Isabelle Martineau

The Attitude of Canadian Nurses Towards Advance Directives

This article seeks to shed light on the beliefs that influence nurses’ intention of respecting or not respecting an advance directive document, namely a living will or a durable power of attorney. Nurses’ beliefs were measured using a 44-statement questionnaire. The sample was made up of 306 nurses working either in a long-term care centre or in a hospital centre offering general and specialized care in the province of Québec. The results indicate that nurses have a strong intention of complying with advance directives written by patients. The analysis also shows that four variables determine the strength of this intention: respect for autonomy; the location of the workplace; justice; and the dimension of relationships and emotions. Although these documents favour the expression of patients’ wishes, nurses should be aware that they do not systematically guarantee respect of a patient’s autonomy, nor do they replace a relationship based on trust between patients and health care professionals.

STUDIES OF THE GUINEA PIG ADRENAL CYTOCHROME P450c17 cDNA

Cytochrome P450c17 is a single enzyme that catalyzes two successive reactions within the delta 5 and delta 4 pathways. The proteins expressed with human, bovine, and rat cDNAs convert both pregnenolone and progesterone into delta 5-delta 4-C19 steroids, although the rat cDNA prefers the delta 4 pathway. Our results showed that the guinea pig adrenal possesses the enzymatic machinery to produce C19 steroids and suggest that the lyase activity plays a major role in regulating these syntheses. To obtain more information on the structure-function relationship we isolated a full-length cDNA clone encoding guinea pig P450c17. Northern blots of total RNA extracted from the testis, ovary, and adrenals of the guinea pig show that the P450c17 cDNA hybridized with a predicted 1.8-kb mRNA and with two other mRNAs of 3 and 4 kb. No signal other than the 1.8-kb mRNA was observed in the human adrenocortical NCI-H295 cells. Activation of the cAMP-dependent protein kinase A pathway increased the levels of the three mRNAs. Transfection of vectors expressing guinea pig P450c17 cDNA into nonsteroidogenic cells confers 17 alpha-hydroxylase and 17,20-lyase activities, showing that a single protein in the guinea pig supports both activities. However, the analysis of the enzymatic properties showed that the guinea pig P450c17 recombinant, in contrast to the human, supports hydroxylase and lyase activities only with delta 4 substrates. These results were further confirmed with isolated guinea pig adrenocortical cells. Our data demonstrate, first, that guinea pig P450c17 cDNA hybridizes with three different transcripts and second, that the expressed protein has characteristics associated exclusively with the guinea pig enzyme.

Psychosocial determinants of physicians’ intention to practice euthanasia in palliative care

BackgroundEuthanasia remains controversial in Canada and an issue of debate among physicians. Most studies have explored the opinion of health professionals regarding its legalization, but have not investigated their intentions when faced with performing euthanasia. These studies are also considered atheoretical. The purposes of the present study were to fill this gap in the literature by identifying the psychosocial determinants of physicians’ intention to practice euthanasia in palliative care and verifying whether respecting the patient’s autonomy is important for physicians.MethodsA validated anonymous questionnaire based on an extended version of the Theory of Planned Behavior was mailed to a random sample of 445 physicians from the province of Quebec, Canada.ResultsThe response rate was 38.3% and the mean score for intention was 3.94 ± 2.17 (range: 1 to 7). The determinants of intention among physicians were: knowing patients’ wishes (OR = 10.77; 95%CI: 1.33-86.88), perceived behavioral control—physicians’ evaluation of their ability to adopt a given behavior—(OR = 4.35; 95%CI: 1.44-13.15), moral norm—the appropriateness of adopting a given behavior according to one’s personal and moral values—(OR = 3.22; 95%CI: 1.29-8.00) and cognitive attitude—factual consequences of the adoption of a given behavior—(OR = 3.16; 95%CI: 1.20-8.35). This model correctly classified 98.8% of physicians. Specific beliefs that might discriminate physicians according to their level of intention were also identified. For instance, physicians’ moral norm was related to the ethical principle of beneficence.ConclusionsOverall, physicians have weak intentions to practice euthanasia in palliative care. Nevertheless, respecting patients’ final wishes concerning euthanasia seems to be of particular importance to them and greatly affects their motivation to perform euthanasia.

Psychosocial determinants of nurses’ intention to practise euthanasia in palliative care

Background: Most studies on euthanasia fail to explain the intentions of health professionals when faced with performing euthanasia and are atheoretical. Research objective: The purpose of this study was to identify the psychosocial determinants of nurses’ intention to practise euthanasia in palliative care if it were legalised. Research design: A cross-sectional study using a validated anonymous questionnaire based on an extended version of the Theory of Planned Behaviour. Participants and research context: A random sample of 445 nurses from the province of Quebec, Canada, was selected for participation in the study. Ethical considerations: The study was reviewed and approved by the Ethics Committee of the Centre hospitalier universitaire de Québec. Findings: The response rate was 44.2% and the mean score for intention was 4.61 ± 1.90 (range: 1–7). The determinants of intention were the subjective (odds ratio = 3.08; 95% confidence interval: 1.50–6.35) and moral (odds ratio = 2.95; 95% confidence interval: 1.58–5.49) norms. Specific beliefs which could discriminate nurses according to their level of intention were identified. Discussion: Overall, nurses have a slightly positive intention to practise euthanasia. Their family approval seems particularly important and also the approval of their medical colleagues. Nurses’ moral norm was related to beneficence, an ethical principle. Conclusion: To our knowledge, this is the first study to identify nurses’ motivations to practise euthanasia in palliative care using a validated psychosocial theory. It also has the distinction of identifying the ethical principles underlying nurses’ moral norm and intention.

Molecular cloning and expression of guinea pig cytochrome P450c21 cDNA (steroid 21-hydroxylase) isolated from the adrenals.

In mammals, the P450c21 enzyme mediates 21-hydroxylase activity by transforming progesterone and 17-hydroxyprogesterone into deoxycorticosterone (DOC) and 11-deoxycortisol (11-DOC), respectively. Previous studies have shown that among the adrenal steroid hydroxylase enzymes involved in C19 steroid and glucocorticoid syntheses, P450c21 plays an important role, because it is localized at the key branch between glucocorticoids and C19 steroid production. Its implication in congenital adrenal hyperplasia is also of great clinical interest. In this study, in addition to describing the isolation of the P450c21 cDNA from guinea pig (GP) adrenal and comparing it to those from other species, we report on its tissue-distribution and on the activity of the recombinant protein towards progesterone and 17-hydroxyprogesterone. The guinea pig P450c21 includes the full-length coding region (1464 nucleotide) that is translated to a protein of 488 amino acids. The clone shares highly conserved regions with other species. The guinea pig P450c21 cDNA hybridized with a major transcript of 2.1kb and with two minor related transcripts of 1.8 and 1.5 kb and was found to be adrenal-specific among the various tissues analyzed. Characterization of the enzymatic activity by transient transfection of the guinea pig P450c21 cDNA in human embryonic kidney 293 cells indicated a net preference for the 21-hydroxylation of 17-hydroxyprogesterone in comparison to the progesterone substrate. Assays showed a maximum conversion rate of 12.5% for the conversion of progesterone into deoxycorticosterone (mineralocorticoid pathway), whereas the guinea pig P450c21 demonstrated a higher activity with 17alpha-hydroxyprogesterone, with 55% of 11-deoxycortisol formation (glucocorticoid pathway) after 48 h. Adrenocorticotropin and an analogue of the second messenger cyclic adenosine monophosphate specifically increased the abundance of P450c21 mRNA levels in guinea pig adrenal cells.