Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024591 (malignant hyperthermia)
 2,353 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Myotonic dystrophy (MD) is a muscle disorder characterized by progressive muscle wasting and weakness, and is the most common form of muscular dystrophy that begins in adulthood, often after pregnancy. MD might be related to occurrence of malignant hyperthermia. Therefore, the cesarean section is often performed for the parturient with MD. We had an experience of combined spinal-epidural anesthesia for cesarean section in a parturient complicated with MD. A 40-year-old woman had rhabdomyolysis caused by ritodrine at 15-week gestation and was diagnosed as MD by electromyography. Her first baby died due to respiratory failure fourth day after birth. She had hatchet face, slight weakness of her lower extremities, and easy fatigability. Her manual muscle test was 5/5 at upper extremities and 4/5 at lower extremities. She underwent emergency cesarean section for premature rupture of the membrane, weak pain during labor, and obstructed labor at 33-week gestation. We placed an epidural catheter from T12/L1 and punctured arachnoid with 25 G spinal needle. We performed spinal anesthesia using 0.5% hyperbaric bupivacaine 1.5 ml and epidural anesthesia using 2% lidocaine 6 ml. Her anesthetic level reached bilaterally to T7 and operation started 18 minutes after combined spinal-epidural anesthesia. Her baby was born 23 minutes after the anesthesia. As her baby was 1/5 at Apgar score, the baby was tracheally intubated and artificially ventilated. The cesarean section was finished in 33 minutes uneventfully. She had no adverse events and was discharged on the 8th postoperative day. Later her baby was diagnosed as congenital MD by gene analysis. Combined spinal-epidural anesthesia with the amide-typed local anesthetic agents could be useful and safe for cesarean section in the parturient with MD.
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PMID:[Combined spinal-epidural anesthesia for cesarean section in a parturient with myotonic dystrophy]. 2071 26

The muscular dystrophies are inherited myogenic disorders characterized by progressive muscle wasting and weakness of variable distribution and severity. They can be subdivided into several groups, including congenital forms, in accordance with the distribution of predominant muscle weakness: Duchenne/Becker; limb-girdle; Fukuyama type congenital muscular dystrophy; Emery-Dreifus; facioscapulohumeral; oculopharyngeal; myotonic dystrophy, et al. Muscular dystrophies are susceptible to perioperative respiratory, cardiac and other complications, such as rhabdomyolysis. Halogenated inhalational anesthetic agents have been implicated as a cause of acute rhabdomyolysis that resembles malignant hyperthermia. Depolarizing neuromuscular blocking drugs that cause rhabdomyolysis are contraindicated in these patients. Recommendations are proposed for the safe anesthetic management of these patients.
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PMID:[Anesthesia preoperative preparation of muscular dystrophy]. 2085 62

The type 1 isoform of the ryanodine receptor (RYR1) is the Ca(2+) release channel of the sarcoplasmic reticulum (SR) that is activated during skeletal muscle excitation-contraction (EC) coupling. Mutations in the RYR1 gene cause several rare inherited skeletal muscle disorders, including malignant hyperthermia and central core disease (CCD). The human RYR1(I4898T) mutation is one of the most common CCD mutations. To elucidate the mechanism by which RYR1 function is altered by this mutation, we characterized in vivo muscle strength, EC coupling, SR Ca(2+) content, and RYR1 Ca(2+) release channel function using adult heterozygous Ryr1(I4895T/+) knock-in mice (IT/+). Compared with age-matched wild-type (WT) mice, IT/+ mice exhibited significantly reduced upper body and grip strength. In spite of normal total SR Ca(2+) content, both electrically evoked and 4-chloro-m-cresol-induced Ca(2+) release were significantly reduced and slowed in single intact flexor digitorum brevis fibers isolated from 4-6-mo-old IT/+ mice. The sensitivity of the SR Ca(2+) release mechanism to activation was not enhanced in fibers of IT/+ mice. Single-channel measurements of purified recombinant channels incorporated in planar lipid bilayers revealed that Ca(2+) permeation was abolished for homotetrameric IT channels and significantly reduced for heterotetrameric WT:IT channels. Collectively, these findings indicate that in vivo muscle weakness observed in IT/+ knock-in mice arises from a reduction in the magnitude and rate of RYR1 Ca(2+) release during EC coupling that results from the mutation producing a dominant-negative suppression of RYR1 channel Ca(2+) ion permeation.
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PMID:Muscle weakness in Ryr1I4895T/WT knock-in mice as a result of reduced ryanodine receptor Ca2+ ion permeation and release from the sarcoplasmic reticulum. 2114 47

A combination of electrophysiological and genetic studies has resulted in the identification of several skeletal muscle disorders to be caused by pathologically functioning ion channels and has led to the term channelopathies. Typical hereditary muscle channelopa thies are congenital myasthenic syndromes, non-dystrophic myotonias, periodic paralyses, malignant hyperthermia, and central core disease. Most muscle channelopathies are commonly considered to be benign diseases. However, life-threatening weakness episodes or progressive permanent weakness may make these diseases severe, particularly the periodic paralyses (PP). Even in the typical PP forms characterized by episodic occurrence of weakness, up to 60% of the patients suffer from permanent weakness and myopathy with age. In addition, some PP patients present with a predominant progressive muscle weakness phenotype. The weakness can be explained by strongly depolarized fibers that take up sodium and water and that are electrically inexcitable. Drugs that repolarize the fiber membrane can restore muscle strength and may prevent progression.
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PMID:State of the art in hereditary muscle channelopathies. 2131 17

We present here the case of a 33-month-old male patient with Wolf-Hirschhorn syndrome (WHS) and who underwent tympanoplasty and myringotomy. WHS is caused by a rare chromosomal abnormality, which is the deletion of the short arm of chromosome number 4. The typical craniofacial features of WHS patients such as micrognathia, microcephaly and the muscular weakness can make using neuromuscular blocking agents and performing intubation difficult. Moreover, there are a few previous case reports showing that malignant hyperthermia occurred during and after an operation in which the anesthesia was done with inhalation agents, so special anesthetic care is needed when operating on a WHS patient. By carefully intubating the patient and using total intravenous anesthesia, we performed successful anesthesia without any complications. We describe here the anesthetic management of a WHS patient and we review the relevant literature.
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PMID:Anesthetic experience using total intra-venous anesthesia for a patient with Wolf-Hirschhorn syndrome -A case report-. 2139 Jan 67

We gave general anesthesia to a patient with scoliosis combined with central core disease (CCD). CCD is a slowly progressive autosomal dominant congenital myopathy. CCD is presented typically in infancy with hypotonia and delay of motor development, characterized by predominantly proximal weakness pronounced in the hip girdle. Orthopedic complications are common with congenital dislocation of the hips, scoliosis and foot deformity. CCD is due to mutations in the skeletal muscle ryanodine receptor (RYR1) gene at chromosome 19q13.1, which is also implicated in the malignant hyperthermia (MH). A patient with CCD is at risk of MH, with an abnormal response to suxamethonium and volatile anesthetics. The anesthetist ought to be aware of the diagnosis of CCD and to plan anesthetic management accordingly, avoiding potentially MH-triggering agents. We used total intravenous anesthesia (TIVA) in this case, and he showed no MH symptoms perioperatively. This report demonstrates that anesthesia in a patient with CCD could be successfully maintained with TIVA.
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PMID:[Anesthetic management for a patient with scoliosis combined with central core disease]. 2152 May 99

Malignant hyperthermia (MH) is a pharmacogenetic, autosomal dominantly inherited disorder of skeletal muscle triggered by volatile anesthetics and infrequently by extreme exertion and heat exposure. MH has variable penetrance with an incidence ranging from 1 in 5000 to 1 in 50,000-100,000 anesthesias. Mutations in the ryanodine receptor gene, RYR1, are found in 50-70% of cases. We hypothesized that a portion of patients with drug-induced muscle diseases, unrelated to anesthesia, such as severe statin myopathy, have underlying genetic liability that may include RYR1 gene mutations. DNA samples were collected from 885 patients in 4 groups: severe statin myopathy (n=197), mild statin myopathy (n=163), statin-tolerant controls (n=133), and non-drug-induced myopathies of unknown etiology characterized by exercise-induced muscle pain and weakness (n=392). Samples were screened for 105 mutations and variants in 26 genes associated with 7 categories of muscle disease including 34 mutations and variants in the RYR1 gene. Disease-causing mutations or variants in RYR1 were present in 3 severe statin myopathy cases, 1 mild statin myopathy case, 8 patients with non-drug-induced myopathy, and none in controls. These results suggest that disease-causing mutations and certain variants in the RYR1 gene may contribute to underlying genetic risk for non-anesthesia-induced myopathies and should be included in genetic susceptibility screening in patients with severe statin myopathy and in patients with non-statin-induced myopathies of unknown etiology.
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PMID:Genetic risk for malignant hyperthermia in non-anesthesia-induced myopathies. 2179 85

A 49-year-old female with mitochondrial encephalomyopathy underwent laparoscopic cholecystotomy. She had some characteristic clinical symptoms, including muscle weakness, deafness, hemianopia and elevation of lactic acid level in the blood. It has been considered that problems of anesthesia for patient with mitochondrial encephalomyopathy are relevant to malignant hyperthermia, respiratory depression due to muscle weakness and probability of hyperlactacidemia. Anesthesia was induced with propofol, remifentanil and rocuronium, and maintained with continuous infusion of propofol and remifentanil, with administration of rocuronium under neuromuscular monitoring throughout the surgery. Arterial blood gases and pH were checked and acetated electrolyte solution was infused mainly during surgery. No complications occurred during anesthesia and this patient showed smooth recovery from anesthesia. Her postoperative course was uneventful.
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PMID:[Total intravenous anesthesia for a patient with mitochondrial encephalomyopathy who underwent laparoscopic cholecystotomy]. 2186 26

Congenital myopathies describe a group of inherited muscle disorders with neonatal or infantile onset typically associated with muscle weakness, respiratory involvement and delayed motor milestones. We previously reported a novel congenital myopathy in an inbred Samaritan family. All patients displayed severe neonatal hypotonia and respiratory distress, and unlike other congenital myopathies, a constantly improving health status. As clinical and pathological data did not point to preferential candidate genes, we performed exome sequencing complemented by linkage analysis to identify the mutation causing the benign Samaritan congenital myopathy. We identified the homozygous p.Tyr1088Cys mutation in RYR1, encoding the skeletal muscle ryanodine receptor. This sarcoplasmic reticulum calcium channel is a key regulator of excitation-contraction coupling (ECC). Western blot and immunohistofluorescence revealed a significant decrease of the RYR1 protein level and an abnormal organization of skeletal muscle triad markers as caveolin-3, dysferlin and amphiphysin 2. RYR1 mutations are associated with different myopathies and malignant hyperthermia susceptibility. The index patient had mild hyperthermia following anesthesia, indicating that the inbred Samaritan population might be a risk group for this disorder. Our results suggest an aberrant ECC as the primary cause of this disease, and broaden the clinical consequences of RYR1 defects.
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PMID:Samaritan myopathy, an ultimately benign congenital myopathy, is caused by a RYR1 mutation. 2275 22

Duchenne muscular dystrophy (DMD) causes profound and progressive muscle weakness and loss, resulting in early death. DMD is usually caused by frameshifting deletions in the gene DMD, which leads to absence of dystrophin protein. Dystrophin binds to F-actin and components of the dystrophin-associated glycoprotein complex and protects the sarcolemma from contraction-induced injury. Antisense oligonucleotide-mediated exon skipping is a promising therapeutic approach aimed at restoring the DMD reading frame and allowing expression of an intact dystrophin glycoprotein complex. To date, low levels of dystrophin protein have been produced in humans by this method. We performed a small-molecule screen to identify existing drugs that enhance antisense-directed exon skipping. We found that dantrolene, currently used to treat malignant hyperthermia, potentiates antisense oligomer-guided exon skipping to increase exon skipping to restore the mRNA reading frame, the sarcolemmal dystrophin protein, and the dystrophin glycoprotein complex in skeletal muscles of mdx mice when delivered intramuscularly or intravenously. Further, dantrolene synergized with multiple weekly injections of antisense to increase muscle strength and reduce serum creatine kinase in mdx mice. Dantrolene similarly promoted antisense-mediated exon skipping in reprogrammed myotubes from DMD patients. Ryanodine and Rycal S107, which, like dantrolene, targets the ryanodine receptor, also promoted antisense-driven exon skipping, implicating the ryanodine receptor as the critical molecular target.
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PMID:Dantrolene enhances antisense-mediated exon skipping in human and mouse models of Duchenne muscular dystrophy. 2324 44


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