Biomedical subjects

G Dionne

Publications and source records attributed to G Dionne.

29 records · Page 2Linked to original sources

PubMed1988

Vaccination against lethal coronavirus-induced encephalitis with a synthetic decapeptide homologous to a domain in the predicted peplomer stalk.

A surface probability method was used to select a decapeptide homologous to residues 993 to 1002 of the peplomer protein E2 of murine hepatitis virus strain JHM, a neurotropic coronavirus. This sequence of amino acids corresponded to a minor peak on a hydrophilicity plot. Immunization of mice with the chemically synthesized peptide coupled to keyhole limpet hemocyanin elicited high levels of neutralizing antibody and protected against lethal virus challenge. Protection correlated with a critical level of antipeptide antibody, which could be reached after a single inoculation. These results suggest that an appropriate antibody response to a highly restricted, surface-exposed domain of this viral protein is critical in determining the outcome of infection of the central nervous system. This sequence is located in the C-terminal fifth of the E2 peplomers, between two predicted coiled-coil structures.

Antibodies, Viral↗

PubMed1987

More on the geographical distribution of physicians.

This paper presents more empirical evidence on the geographical distribution of physicians. Probit procedure and data for the Province of Quebec were used. The results are consistent with the standard location theory and therefore with those of Newhouse et al. (1982a). They also show that quality of leisure, distance to central city areas, average income and presence of a hospital are significant in explaining the probability that at least one physician (specialist or general practitioner) is present in a given town. Other variables were also considered.

Demography↗

PubMed1987

Identification of a synthetic peptide as part of a major neutralization epitope of respiratory syncytial virus.

A 7000 Mr cleavage fragment of the F1 subunit that carries the major neutralization epitope has been identified by chemical and enzymatic cleavage of the fusion protein of respiratory syncytial (RS) virus (Long strain) with an efficient RS virus-neutralizing monoclonal antibody. Based on the published mRNA-deduced sequence of the A2 strain, coupled to the hydropathicity profile and prediction of protein conformation, the neutralization epitope has tentatively been localized on the first third of the F1 protein N-terminal, probably in the region of amino acids 215Ser to 236Glu. Analysis of three peptides covering different portions of the 212Cys to 236Glu region of the F1 fusion protein identified a peptide (Cys X 216Asn to 236Glu) that reacted strongly with the neutralizing monoclonal antibody and that was efficient in blocking neutralization and in plaque-reducing assays, confirming that the neutralization epitope was localized in that region. Further analysis with two other synthetic peptides (212Cys to 222Glu and Cys X 221Ile to 236Glu) indicated that the dodecapeptide Ile-Glu-Phe-Gln-Lys-Asn-Asn-Arg-Leu-Leu-Glu mimicked either the whole or a major part of the neutralization epitope. This opens a promising avenue for the simple design of a synthetic peptide vaccine to control RS virus infection.

Antibodies↗

PubMed1986

Synthesis and activity profiles of atrial natriuretic peptide (ANP) analogs with reduced ring size.

Three deletion analogs of the atrial natriuretic peptide, [desGly-120]-ANP(103-126), [desLeu119, desGly120]ANP(103-126) and [desGly118,120,-desLeu119]-ANP(103-126), were synthesized by the solid-phase method. Successive elimination of the non-functional residues in positions 120-118 of the peptide sequence resulted in a progressive potency reduction in the rabbit aorta assay, in the bioassay monitoring suppression of aldosterone secretion from bovine zona glomerulosa cells and in a binding assay based on displacement of radioiodinated ANP(101-126) from bovine zona glomerulosa cell membranes. The fact that the deletion analogs showed quantitatively different relative potencies in each of the three in vitro assay systems was interpreted as further evidence in support of the existence of two or more classes of ANP receptors or binding sites.

Adrenal Glands↗

PubMed1986

Ligand-receptor interactions via hydrogen-bond formation. Synthesis and pharmacological evaluation of pyrrolo and pyrido analogues of the cardiotonic agent 7-hydroxycyclindole.

The syntheses of N,N-dimethyl-6,7,8,9-tetrahydro-3H,10H-pyrrolo[3,2-a] carbazol-7-amine (8), N,N-dimethyl-7,8,9,10-tetrahydro-11H-pyrido[3,2-a] carbazol-8-amine (9a), and the N,N,11-trimethyl analogue (9b) are described. The in vitro inotropic activity of these compounds, as well as the known cardiotonics amrinone and 7-hydroxycyclindole (7), was investigated. Compound 8, a pyrrolo analogue of 7, was devoid of inotropic activity, while the pyrido analogues 9 were equiactive to 7 and amrinone. These results suggest that the hydroxyl group of 7 functions as an H-bond acceptor, rather than a donor, and that on interaction of 7, and the pyrido analogues 9, with a common receptor, an orbital occupied by one of the oxygen lone pair electrons of 7 must assume the same orientation as the orbital occupied by the pyridine nitrogen lone pair.

Aminopyridines↗

PubMed1985

Doctors and their workshops. A review article.

In this paper we present a theoretical framework for reviewing the main points treated by Pauly (1980). Moreover, we isolate the issues which still need further research. Finally, we briefly discuss the overall message of Pauly's book: Standard Economic Models Can Explain Behavior in the Medical Care Industry.

Canada↗

PubMed1985

Patient mobility for elective surgical interventions.

In this study, we address the question of patient mobility by defining three types of mobility and testing them with a Probit model. First, we have forced mobility (shortage of resources), second, physician-induced mobility (hospital affiliations) and finally, the mobility chosen by patients. We isolate explanatory variables for observed patient mobility for the year 1977-1978 in Quebec, Canada, and present the results for two specific surgical interventions. We found that forced and induced mobility are statistically significant in explaining the movements of patients in search of specific medical services. However, the mobility chosen by patients requires further investigation.

Adolescent↗

PubMed1974