PubMed Health⌕ Search

Biomedical subjects

M Sabourin

Publications and source records attributed to M Sabourin.

13 recordsLinked to original sources
PubMed2002

Introducing printed postpartum orders for measles-mumps-rubella vaccination: a qualitative study.

OBJECTIVE: After introducing printed postpartum orders at our centre, we observed a large increase in measles-mumps-rubella (MMR) vaccination of susceptible women. The objective of this study was to ascertain factors responsible for the success of our approach and to identify potential obstacles so as to facilitate the implementation of similar policies at other hospitals. METHODS: For this qualitative study, taped semi-structured interviews were carried out with physicians, nurses, and a ward clerk regarding their views on postpartum MMR vaccination and on various aspects of implementing a printed postpartum order sheet that included MMR vaccination of susceptible women. Interviews were transcribed and the responses classified by theme. Thematic analysis was used to identify strengths and weaknesses of this approach. RESULTS: Following implementation of printed postpartum orders that included MMR vaccination of susceptible women, the proportion of eligible women vaccinated increased from 12.1 to 81.7% (risk ratio 6.8, 95% confidence interval [CI] 3.3, 13.7). While the physician and nursing staff broadly supported this initiative, we identified the need for changes in obstetrical care and documentation: most importantly, a comprehensive protocol with supporting information and guidelines should be provided for postpartum nurses; and a system must be in place to ensure that the completed antenatal record, including screening test results, be available in the expected hospital of delivery by the late second trimester. CONCLUSION: Previously undocumented claims that standing orders for postpartum MMR vaccination will increase the rate of vaccination of susceptible women have now been substantiated at one centre. Nevertheless, careful infrastructure and systems changes are required to ensure implementation of such orders.

Female↗
PubMed2000

Sensitivity of human type II topoisomerases to DNA damage: stimulation of enzyme-mediated DNA cleavage by abasic, oxidized and alkylated lesions.

Type II topoisomerases are essential enzymes that are also the primary cellular targets for a number of important anticancer drugs. These drugs act by increasing levels of topoisomerase II-mediated DNA cleavage. Recent studies indicate that endogenous forms of DNA damage, such as abasic sites and base mismatches, also stimulate the DNA scission activity of the enzyme. To extend our understanding of how type II topoisomerases react to DNA damage, the effects of abasic sites, and oxidized and alkylated bases on DNA cleavage mediated by human topo-isomerase IIalpha and beta were determined. Based on experiments that incorporated random abasic sites into plasmid DNA, human type II enzymes can locate lesions even within a background of several thousand undamaged base pairs. As determined by experiments that utilized site-specific forms of DNA lesions, oxidized or monoalkylated purines that allow base pairing and induce little distortion in the double helix have modest effects on topoisomerase II-mediated DNA cleavage. In contrast, 1,N(6)-ethenoadenine, a bulky lesion that disrupts base pairing, enhanced DNA cleavage approximately 10-fold. 1,N(6)-Ethenoadenine is the first lesion found to rival the stimulatory effects of apurinic sites on the DNA scission activity of eukaryotic type II topoisomerases.

Adenine↗
PubMed2000

Characterization of hch, the Podospora anserina homolog of the het-c heterokaryon incompatibility gene of Neurospora crassa.

The het-c locus controls heterokaryon formation in Neurospora crassa. It is subject to balancing selection operating to maintain polymorphism at that locus in natural populations. We have isolated hch, the het-c homolog from the related species Podospora anserina (hch for het-c homolog), in order to determine if this gene also functions as a het gene in that species. The het-c and hch sequences are highly similar but differ in the region defining allele specificity in N. crassa het-c. Analysis of hch variability in 11 natural P. anserina isolates with different het genotypes revealed no polymorphism. This suggested that hch does not function as a het gene. However, heterologous expression of the N. crassa het-cPA allele in P. anserina triggers a growth defect reminiscent of the het-c incompatibility reaction.

Amino Acid Sequence↗
PubMed1999

[The evolution of ethical standards in the practice of psychology: a reflection on the APA Code of Ethics].

After briefly describing the need for ethics in the development of professional regulation and analyzing the historical emergence of codes of ethics, the goal of this paper is to scrutinize the process by which the American Psychological Association developed its own Code of Ethics and proceeded to revise it periodically. Different lessons can be derived from these efforts and from the criticisms that were formulated. The need for international standards in professional and research ethics is then considered, and the results of a recent study on this subject are presented. Five major conclusions can be derived from the preceding analysis: (1) Codes of ethics can help professional recognition by stressing the importance given to the protection of the public, (2) the development of a code of ethics is usually related to the advancement of professional practice, (3) ethical standards should be in tune with the cultural values and the belief system of a given community, (4) a well-balanced code should incorporate both general aspirational principles and enforceable standards, and (5) the method used to define principles and standards should be empirically based.

Ethics, Professional↗
PubMed1998

A mutant yeast topoisomerase II (top2G437S) with differential sensitivity to anticancer drugs in the presence and absence of ATP.

To further characterize the mechanistic basis for cellular resistance/hypersensitivity to anticancer drugs, a yeast genetic system was used to select a mutant type II topoisomerase that conferred cellular resistance to CP-115,953, amsacrine, etoposide, and ellipticine. The mutant enzyme contained a single point mutation that converted Gly437 --> Ser (top2G437S). Purified top2G437S displayed wild-type enzymatic activity in the absence of drugs but exhibited two properties that were not predicted by the cellular resistance phenotype. First, in the absence of ATP, it was hypersensitive to all of the drugs examined and hypersensitivity correlated with increased drug affinity. Second, in the presence of ATP, top2G437S lost its hypersensitivity and displayed wild-type drug sensitivity. Since the resistance of yeast harboring top2G437S could not be explained by alterations in enzyme-drug interactions, physiological levels of topoisomerase II were determined. The Gly437 --> Ser mutation reduced the stability of topoisomerase II and decreased the cellular concentration of the enzyme. These findings suggest that the physiological drug resistance phenotype conferred by top2G437S results primarily from its decreased stability. This study highlights the need to analyze both the biochemistry and the physiology of topoisomerase II mutants with altered drug sensitivity in order to define the mechanistic bridge that links enzyme function to cellular phenotype.

Adenosine Triphosphate↗
PubMed1979

Effects of active and passive EMG biofeedback training on performance of motor and cognitive tasks.

The goal of this study was to compare the effects of general relaxation (passive group) and neuromuscular tension control (active group), both using EMG biofeedback techniques, on the performance of memorization, simple reaction time, and rotary pursuit. 18 subjects were given five consecutive daily sessions of training or were placed under control conditions, after which their performance on these various tasks was evaluated. Results indicate that control of neuromuscular tension seemed to facilitate performance on all tasks over that of the control group. Except for simple reaction time, there was no difference between the "active" and "passive" groups. The results are interpreted in terms of factors in selection of subjects and experimental conditions.

Biofeedback, Psychology↗
PubMedDate not supplied

Oxidative metabolism of 1-(2-chloroethyl)-3-alkyl-3- (methylcarbamoyl)triazenes: formation of chloroacetaldehyde and relevance to biological activity.

(Methylcarbamoyl)triazenes have been shown to be effective cancer chemotherapeutic agents in a number of biological systems. Because of their chemical stability, it is likely that their activity in vivo is the result of a metabolic activation process. Previous studies have shown that 1-(2-chloroethyl)-3-methyl-3-(methylcarbamoyl)triazene (CMM) and 1-(2-chloroethyl)-3-benzyl-3-(methylcarbamoyl)triazene (CBzM) are metabolized by rat liver microsomes in the presence of NADPH to yield the ((hydroxymethyl)carbamoyl)triazene analogs of the parent compounds. The present studies show that both compounds are also oxidized at the chloroethyl substituent to yield chloroacetaldehyde and a substituted urea. In the case of CBzM metabolism, 47% of the metabolized parent compound was recovered as benzylmethylurea, 8% was recovered as benzylurea, and 26% was recovered as the ((hydroxymethyl)carbamoyl)-triazene and carbamoyltriazene metabolites. These results suggest that the chloroethyl group is the favored initial site of metabolism. In reaction mixtures containing initial concentrations of 300 microM CBzM, 78 microM chloroacetaldehyde was produced, as compared to 58 microM chloroacetaldehyde produced from the metabolism of 300 microM CMM. The formation of chloroacetaldehyde, a known mutagenic DNA alkylating agent, may explain the biological activity of these compounds.

Acetaldehyde↗