Analysis of human cultured myotubes responses mediated by ryanodine receptor 1.

Malignant hyperthermia is a life-threatening condition caused by autosomal dominant mutations in the ryanodine receptor type 1 gene. Identifying patients predisposed to malignant hyperthermia is done through the Ca-induced Ca release test in Japan. We examined the intracellular calcium concentration in human cultured muscle cells and compared the sensitivity of myotubes to ryanodine receptor type 1 activators based on the Ca-induced Ca release rate.

Safety of the inter-nipple line hand position landmark for chest compression.

Background: No previous study has investigated the safety of hand position during chest compression determined by the inter-nipple line, in which the heel of one hand is positioned on the centre of the chest between the nipples, from the standpoint of prevention of organ injury.

Methods: We measured the distance from the xiphisternal junction to the inter-nipple line (dN) in 1000 surgical patients and the heel length (H) of hands in 100 healthy volunteers, then used the formula H/2-dN to determine the amount of deviation when the heel of the rescuer's hand extended to the xiphoid process (D). Next, 100 surgical patients were randomly assigned to 18 anaesthesiologists, who placed the heels of their hands on the sternum for validation.

Assessment of internal thoracic artery patency with transesophageal echocardiography during coronary artery bypass graft surgery.

Objective: The purpose of this study was to evaluate intraoperative transesophageal echocardiography (TEE) for assessing patency of internal thoracic artery grafts.

Design: A retrospective study.

Setting: A university hospital.

Effects of propofol on calcium homeostasis in human skeletal muscle.

Malignant hyperthermia is a pharmacogenetic skeletal muscle disorder of intracellular calcium (Ca2+) homeostasis with an autosomal dominant inheritance. The objective of this study was to investigate the safety of propofol by investigating its effects on calcium homeostasis and its effect sites in human skeletal muscles. Muscle specimens were obtained from 10 individuals with predisposition to malignant hyperthermia.

Thiamylal and thiopental attenuate beta-adrenergic signaling pathway by suppressing adenylyl cyclase in rat ventricular myocytes.

The effects of intravenous anesthetics on myocytes have not been fully elucidated. To investigate the effects of various intravenous anesthetics such as fentanyl, morphine, ketamine, diazepam, midazolam, thiamylal, and thiopental on the beta-adrenergic signaling pathway, we measured isoproterenol-stimulated cyclic adenosine monophosphate (cAMP) production in freshly isolated rat ventricular myocytes. Fentanyl, morphine, ketamine, diazepam, and midazolam did not significantly affect isoproterenol-stimulated cAMP production.