China
Africa
Explore chapters and articles related to this topic
Targeting the Nervous System
Published in Nathan Keighley, Miraculous Medicines and the Chemistry of Drug Design, 2020
Antagonists of the nicotinic cholinergic receptor are also medicinally beneficial. They are present in nerve synapses at neuromuscular junctions and can be used as blocking agents. In the 16th century, when Spanish soldiers, known as conquistadors, invaded South America, the indigenous people used poisonous arrows in retaliation. The Indians used a crude dried extract from a plant called Chondrodendron tomentosum, which caused paralysis and stopped the heart. This extract is known as curare, consisting of a mixture of compounds, but later discovered that the active component was an antagonist of acetylcholine, which blocks nerve transmissions from nerve to muscle. This compound is called tubocurarine, and with controlled dose levels, is found to be medicinally useful for relaxing the abdominal muscles before surgery therefore a lower dose of general anaesthetic can be used, improving safety of operations. However, side effects on the autonomous nervous system meant that better drugs had to be developed.
Anesthesia and analgesia and the curse of Eve
Published in Michael J. O’Dowd, The History of Medications for Women, 2020
Harold Griffith and Enid Johnson of Montreal, on the advice of Lewis Wright, introduced curare as a muscle relaxant in anesthesia, a significant advance which allowed safer anesthesia (Griffith and Johnson, 1942 pp. 418–20). Curare, an arrow poison extracted from various plants including Strychnos toxifera, was first described in the Western world in 1516 by the Italian, Peter Martyr of d’Anghera, after his observation of its use by native Amerindians (see Hughes, 1989 pp. 257–67 for a good account).
Diagnosis and Differential Diagnosis
Published in Marc H. De Baets, Hans J.G.H. Oosterhuis, Myasthenia Gravis, 2019
Intravenous injection of 1 to 2 mg d-tubocurarine usually provokes generalized weakness and even dyspnea in most MG patients, even if only ocular weakness is clinically manifest.87,88 In normal controls mild ptosis and shaky eye movements may occur especially in women over the age of 50.89 Regional application of curare in a superficial forearm vein after occlusion of the brachial circulation, is followed by conventional nerve stimulation tests and measurement of grip strength.90 The resorption of the locally applied curare is variable and the reliability of this test was disputed.91 In both the systematized and the regional tests, precautions should be taken (assisted ventilation should be possible) in case of hypersensitivity or unwarranted overdosage, which may even occur in the regional test after release of the tourniquet.92 False positive tests were found in other diseases.93
Intravenous magnesium sulphate infusion as first-line therapy in the control of spasms and muscular rigidity in childhood tetanus
Published in Paediatrics and International Child Health, 2019
Preeti Shanbag, Anupama Mauskar, Sanjeevani Masavkar
The goals of therapy include interrupting the production of toxin, neutralising unbound toxin, controlling muscle spasms, maintenance of the airway, the provision of adequate ventilation and managing dysautonomia. Despite a paucity of evidence, benzodiazepines in very high doses have been the mainstay for the control of spasms in tetanus. Diazepam is the most commonly used benzodiazepine, being cheap and available in most resource-limited settings where tetanus is a significant public health problem. Severe spasms necessitate the use of neuromuscular blocking agents such as pancuronium and vecuronium. These are non-depolarising curare-mimetic muscle relaxants which competitively inhibit the nicotinic acetyl-choline receptor at the neuromuscular junction by blocking the binding of acetylcholine [5]. However, their use requires ready access to mechanical ventilation.
Magnesium Sulfate-Induced Motor Evoked Potential Changes
Published in The Neurodiagnostic Journal, 2018
Tucker Johnson, Emily B. Kale, Aatif M. Husain
The neuromuscular effects of magnesium were recognized more than 50 years ago (del Castillo and Engbaek 1954). It was appreciated that magnesium could antagonize the effects of acetylcholine on muscle fibers. Magnesium was noted to have curarine-like effects on neuromuscular transmission that could be overcome by increasing the calcium concentration (del Castillo and Engbaek 1954). It is now recognized that magnesium can enhance effects of inhalational anesthetics and neuromuscular blocking drugs (Herroeder et al. 2011). The onset of potentiation of paralysis is within 3–4 minutes, depending on the dose, and lasts for about 30 minutes (Ghodraty et al. 2012). This time frame of activity is consistent with what was observed in the present case, with changes in MEPs starting about 3.5 minutes after the magnesium sulfate bolus and resolution of the changes in about 20 minutes.
Exploring the role of botulinum toxin in critical care
Published in Expert Review of Neurotherapeutics, 2021
Muhammad Ubaid Hafeez, Michael Moore, Komal Hafeez, Joseph Jankovic
While role of BoNT is well-established in managing focal dystonia, its use for SD is mostly based on case studies [7–9]. Manji et al. reported a highly intractable case of SD in a neonate with retrocollis which improved after local BoNT injections [7]. In a retrospective review of 27 patients with refractory SD, neuromuscular blockade (BoNT or curare drugs) was used in 29.2% cases and was reported successful in 7% cases [9].