Search PubMed⌕ Search

Biomedical subjects

J Drouet

Publications and source records attributed to J Drouet.

71 records · Page 4Linked to original sources
PubMedDate not supplied

[Ciguatera: neurophysiological demonstration of toxicity of several ciquatoxic fractions].

Raw extracts from one Polynesian, frequently ciguatera-inducing fish were submitted to fractional distillation by means of a chromatographic process using a silicic acid column. Three out of the seven fractions split this way exhibited either anticholinesterasic properties, or directly toxic properties at the muscle-cell level: fraction 5, which is not antagonized by atropine, presumably accounts for this direct action, as it competes with calcium at membrane sites. Fraction 6 appears to be more specially responsible for the anticholinesterasic action. It revealed a quaternary ammonium ion in its 6-2 sub-fraction. Fraction 7 shows the same properties as fraction 6, but on a smaller scale.

Action Potentials↗
PubMedDate not supplied

[Histoenzymologic study of anticholinesterase activity of ciguatoxic extracts of Ceochetus striatus (Gunther) and Plectrompus leopardus].

The use of histo-enzymological techniques for visualizing the cholinesterasic spots on the motory plate is turned to account by the authors to point out the inhibition of the cholinesterasic processes, by some fractions of the ciguatoxins at the level of the neuro-mucular synapsis. The results obtained confirm, on one hand, the efficiency of the method to test the anti-cholinesterasic activity of some fractions of the ciguateric extracts, and, on the other hand, enable the establishment of the fact that even clinically non toxic individuals from fishspecies, dwelling in tropical coral biotops, can provoke a slightly marked but real inhibition of the cholinesterases, provided the contact between the fish extract and the neuro-motory plate is long enough in time. This observation reinforces the thesis of the ecological origin of the toxins along the alimentary chain of the reef biocoenosis.

Animals↗
PubMedDate not supplied

[Variation of plasmatic adenosine 3'', 5-cyclic monophosphate in irradiated-enterectomised dogs (author's transl)].

In the irradiated dog at different doses 250-400 R., a level plasma AMPc rise has been shown since the fourth hour with a maximum at 24 hours, returning to normal values about the thirtieth day. In irradiated at 250-300 R and secondarily enterectomised animals, nucleotide level rises 24 hours later, however this phenomenon is less intensive and later irradiated at 350 and 400 R.

Animals↗
PubMedDate not supplied

[Alcyonidium gelatinosum (L.) (Bryozoa) and cutaneous hypersensitivity reactions. Preliminary results of an experimental study].

The appearance of acute eczematous dermatitis in fishermen from the estuary of the Seine, about which the responsibility of Alcyonidium gelatinosum (L.) is still under discussion, led us to estimate the ability of this Bryozoa to induce cutaneous responses of delayed hypersensitivity. Intradermal tests carried out in guinea-pigs after subcutaneous, respiratory or percutaneous sensitization, gave evidence of a clear allergenic ability of this alcyonelline. The deposit of the biological product on normal skin during four consecutive days is enough to induce strong responses of delayed hypersensitivity. This experimental study needs further investigations in which the possible existence of anaphylactic reactions should be confirmed.

Animals↗
PubMedDate not supplied

[Production of monoclonal antibodies against HBs (author's transl)].

Two BALB/c mice were immunized 4 times with a mixture of adw2 and ayw4 subtypes of HBs antigens. Their spleens were then hybridized with mouse myeloma cell line NS1. Using three different radioimmunoassays (RIA), 264 independent hybridomas were screened for anti-HBs activity. By at last one of these techniques, 95% of the colonies were positive. Selected colonies were cloned and supernatants studied by RIA and immunodiffusion techniques for specificity characterisation. Some clones recognised the common "a" subtype, and other were directed to more restricted specificities. Ascites fluid was active on RIA up to 10(7) dilution (up to 29.000 UI/ml). These monoclonal antibodies may be powerful reagent for the diagnosis and understanding of viral hepatitis B.

Animals↗