Physostigmine

Définitions de « physostigmine »

Physostigmine - Nom commun

• Alcaloïde extrait de la fève de Calabar, utilisé notamment en pharmacologie.

  La physostigmine est extraite dʼune fève africaine et a été utilisée comme poison par les autochtones africains.

Étymologie de « physostigmine »

Évolution historique de l’usage du mot « physostigmine » depuis 1800

Citations contenant le mot « physostigmine »

• Chimiste : il a été le premier à synthétiser la physostigmine (*ou ésérine – molécule isolée en 1864 et dont le nom dérive de la fève de Calabar de la plante Eséré), et donc l'un des premiers à ouvrir la voie à la production industrielle des hormones chimiques : stéroïdes, progestérone, testostérone qui a conduit à la cortisone et à la pilule anticonceptionnelle. Il est à l'origine de l'amélioration de millions de vie et n'a fait rien moins que changer le monde.

• The challenger was Percy Lavon Julian, a young, Black chemist at DePauw University in Indiana. Born in 1899 in Alabama as the grandson of former slaves, Julian grew up under Jim Crow laws. He’d been one of the first African Americans to earn a PhD in chemistry, something he did at the University of Vienna after Harvard University’s policies stopped him from continuing his education beyond a master’s degree. Now a research fellow at DePauw, he was collaborating with Viennese chemist Josef Pikl on the same challenge that Robinson had taken on: making physostigmine in the lab.

• In choosing to synthesize physostigmine, Julian was challenging one of the foremost chemists of the day. Sir Robert Robinson had published widely on physostigmine and was working to synthesize the substance himself. Undaunted, Julian set out to get there first. With Pikl, he devised a different approach to creating the alkaloid. The two published articles on their progress, but the ultimate goal remained elusive.

• Physostigmine, isolated from the Calabar bean, had been found by Austrian physiologist Jacob Pal to counter the effects of curare, although it’s mechanism of action was not known. That was only discovered after English pharmacologist Sir Henry Dale determined that curare produces paralysis by blocking the receptor on nerve cells for acetylcholine, the neurotransmitter needed for muscular activity. It is this activity that physostigmine counters by inactivating acetylcholinesterase, the enzyme that normally breaks down acetylcholine. As a result, the concentration of acetylcholine is increased and it displaces curare from the receptor.

• Pediatricians should screen for and discuss the risks from these challenges with their patients. The TikTok Benadryl challenge has resulted in at least one death and significant morbidity. Management includes early recognition of the signs and symptoms of antimuscarinic toxicity (altered mentation, tachycardia, dry mucous membranes, etc.) and providing supportive management with benzodiazepines, sodium bicarbonate, and physostigmine when necessary. Assistance is available by calling your local poison center 800-222-1222.

• With his doctorate in hand, he returned to DePauw to continue his research. In 1935, he earned international acclaim by synthesizing physostigmine from the calabar bean to create a drug treatment for glaucoma, but in spite of his success, the university refused to make him a full professor because of his race.

Traductions du mot « physostigmine »

Sources et ressources complémentaires

• Définitions du Wiktionnaire