Biomedical subjects

Marie José Durand

Publications and source records attributed to Marie José Durand.

3 recordsLinked to original sources

PubMed2003

Specific detection of organotin compounds with a recombinant luminescent bacteria.

Organotin compounds are widely used as biocides in marine and terrestrial environments. Several currently used techniques allow either the measurement of the chemicals or their effects on living organisms. Our current research focuses on the development of a complementary method based on a bacterial bioluminescence-based bioassay for the specific detection of organotin compounds. The performance of the bioassay was assessed. The Escherichia coli bacterial strain used in this study is specific for TBT and DBT (with Cl, Br or I as the halogen group) with the central tin atom important for light production. The assay is conducted after overnight culture of the bacterial strain, followed by 60 min of contact time with the organotin compound for significant light production. The detection limits were found to be 0.08 microM for TBT (26 microgl(-1)) and 0.0001 microM for DBT (0.03 microgl(-1)) with a linear range of one logarithm. The repeatability of the bioassay is 8% and the reproducibility for TBT and DBT was approximately 14%. Lyophilization of the strains did not significantly modify the detection limit as well as the range of detection. Applications of the bioassay to environmental samples are discussed.

Biological Assay↗

PubMed2002

Negotiation-centred versus client-centred: which approach should be used?

For nearly 20 years, Canadian occupational therapists have attached great importance to the client-centred approach within their practice. Professionals have agreed to define this approach through a philosophy built around the concepts of respect, power and partnership. But no reported work has really clarified what is meant by these three fundamental concepts. This article attempts to define the concepts of respect and power in the therapist-client relationship through a review of occupational therapy and related health and social sciences literature. It raises the question: "In the professional-client relationship, should the power reside with the client or is a more balanced approach needed?" This paper also proposes using the term negotiation instead of partnership, since negotiation seems to offer more applications for occupational therapy practice. The objective of the authors who advocate for greater negotiation between client and therapist is to stimulate analysis.

Canada↗

PubMedDate not supplied

Comparison of the spectral emission of lux recombinant and bioluminescent marine bacteria.

The purpose of the present paper was to study the influence of bacteria harbouring the luciferase-encoding Vibrio harveyi luxAB genes upon the spectral emission during growth in batch-culture conditions. In vivo bioluminescence spectra were compared from several bioluminescent strains, either naturally luminescent (Vibrio fischeri and Vibrio harveyi) or in recombinant strains (two Gram-negative Escherichia coli::luxAB strains and a Gram-positive Bacillus subtilis::luxAB strain). Spectral emission was recorded from 400 nm to 750 nm using a highly sensitive spectrometer initially devoted to Raman scattering. Two peaks were clearly identified, one at 491-500 nm (+/- 5 nm) and a second peak at 585-595 (+/- 5 nm) with the Raman CCD. The former peak was the only one detected with traditional spectrometers with a photomultiplier detector commonly used for spectral emission measurement, due to their lack of sensitivity and low resolution in the 550-650 nm window. When spectra were compared between all the studied bacteria, no difference was observed between natural or recombinant cells, between Gram-positive and Gram-negative strains, and growth conditions and growth medium were not found to modify the spectrum of light emission.

Bacillus subtilis↗