Prediction of anesthetic torsadogenicity using a human ventricular cell model.

This simulation study was designed to predict the torsadogenicity of sevoflurane and propofol in healthy control, as well as type 1 and type 2 long QT syndrome (LQT1 and LQT2, respectively), using the O'Hara-Rudy dynamic model. LQT1 and LQT2 models were simulated by decreasing the conductances of slowly and rapidly activating delayed rectifier K currents (I and I, respectively) by 50%, respectively. Action potential duration at 50% repolarization level (APD) and diastolic intracellular Ca concentration were measured in epicardial cell during administration of sevoflurane (1 ~ 5%) and propofol (1 ~ 10 μM).

Severe Calcification of Femoral Arteries Causes Tourniquet Failure Accompanied by Massive Bleeding.

Tourniquet failure is attributed to inadequate tourniquet pressure, inadequate exsanguination, failure to compress medullary vessels within the bone, and incompressible calcified arteries. We herein report a case of massive bleeding using a properly functioning tourniquet in a patient who had bilateral calcified femoral arteries. When incompressible calcified arteries are present, the inflated tourniquet cuff fails to adequately compress the underlying artery, yet acts as an efficient venous tourniquet, which leads to an increase in bleeding.

Propofol, an Anesthetic Agent, Inhibits HCN Channels through the Allosteric Modulation of the cAMP-Dependent Gating Mechanism.

Propofol is a broadly used intravenous anesthetic agent that can cause cardiovascular effects, including bradycardia and asystole. A possible mechanism for these effects is slowing cardiac pacemaker activity due to inhibition of the hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels. However, it remains unclear how propofol affects the allosteric nature of the voltage- and cAMP-dependent gating mechanism in HCN channels.

A Pure Acute Subdural Hematoma Presenting with a Diploic Arteriovenous Fistula: Case Report and Literature Review.

Objective: We report a case of pure acute subdural hematoma (SDH) caused by a diploic arteriovenous fistula (AVF) and it is a first case report as far as we researched it.

Case Presentation: A 19-year-old man was admitted as an emergency to our hospital with headache and nausea. CT scan on hospital admission showed a right acute SDH.

Positive Inotropic Effects of ATP Released the Maxi-Anion Channel in Langendorff-Perfused Mouse Hearts Subjected to Ischemia-Reperfusion.

The organic anion transporter SLCO2A1 constitutes an essential core component of the ATP-conductive large-conductance anion (Maxi-Cl) channel. Our previous experiments using Langendorff-perfused mouse hearts showed that the Maxi-Cl channel contributes largely to the release of ATP into the coronary effluent observed during 10-min reperfusion following a short period (6 min) of oxygen-glucose deprivation. The present study examined the effect of endogenous ATP released Maxi-Cl channels on the left ventricular contractile function of Langendorff-perfused mouse hearts, using a fluid-filled balloon connected to a pressure transducer.

A computational analysis of the effect of sevoflurane in a human ventricular cell model of long QT syndrome: Importance of repolarization reserve in the QT-prolonging effect of sevoflurane.

The slowly and rapidly activating delayed rectifier K channels (I and I, respectively) contribute to the repolarization of ventricular action potential in human heart and thereby determine QT interval on an electrocardiogram. Loss-of-function mutations in genes encoding I and I cause type 1 and type 2 long QT syndrome (LQT1 and LQT2, respectively), accompanied by a high risk of malignant ventricular arrhythmias and sudden cardiac death. This study was designed to investigate which cardiac electrophysiological conditions exaggerate QT-prolonging and arrhythmogenic effects of sevoflurane.

Open-channel blocking action of volatile anaesthetics desflurane and sevoflurane on human voltage-gated K 1.5 channel.

Background And Purpose: Volatile anaesthetics have been shown to differentially modulate mammalian Shaker-related voltage-gated potassium (K 1.x) channels. This study was designed to investigate molecular and cellular mechanisms underlying the modulatory effects of desflurane or sevoflurane on human K 1.

Transient Receptor Potential Canonical Channel Blockers Improve Ventricular Contractile Functions After Ischemia/Reperfusion in a Langendorff-perfused Mouse Heart Model.

Reperfusion of ischemic myocardium is accompanied by intracellular Ca overload, leading to cardiac dysfunction. However, the mechanisms underlying intracellular Ca overload have yet to be fully elucidated. The mechanism may involve the activation of store-operated Ca entry, which is primarily mediated through the transient receptor potential canonical (TRPC) channels.

Interactions of Propofol With Human Voltage-gated Kv1.5 Channel Determined by Docking Simulation and Mutagenesis Analyses.

Propofol blocks the voltage-gated human Kv1.5 (hKv1.5) channel by preferentially affecting in its open state.

[Ruptured Dissecting Aneurysm of M2 Portion of the Middle Cerebral Artery:A Case Report].

A 71-year-old woman presented with a sudden onset of headache and vomiting. Computed tomography(CT)showed diffuse subarachnoid hemorrhage(SAH)that was more severe on the right side. Three-dimensional CT angiography and right carotid angiography(CAG)demonstrated 2-mm microaneurysms at the middle cerebral artery(MCA)bifurcation and anterior communicating artery, with slight narrowing and dilatation of the M2 inferior trunk.

Hyperkalemia caused by rapid red cell transfusion and the potassium absorption filter.

We report a case of transient hyperkalemia during hysterectomy after cesarean section, due to preoperatively undiagnosed placenta accreta that caused unforeseen massive hemorrhage and required rapid red cell transfusion. Hyperkalemia-induced by rapid red cell transfusion is a well-known severe complication of transfusion; however, in patients with sudden massive hemorrhage, rapid red cell transfusion is necessary to save their life. In such cases, it is extremely important to monitor serum potassium levels.

[A case of ganglioglioma extended to the lateral ventricle and associated with neurofibromatosis type 1].

We encountered a rare case of intraventricular ganglioglioma associated with neurofibromatosis type 1. A 42-year-old woman presented with a feeling of heaviness of the head and dizziness. She was diagnosed with neurofibromatosis type 1 because she had multiple subcutaneous neurofibromas and café au lait spots.

Rapid formation of cerebral microbleeds after carotid artery stenting.

Background: Recent studies reported that cerebral microbleeds (CMBs), i.e. small areas of signal loss on T(2)*-weighted gradient-echo (GE) imaging, could develop rapidly after acute ischemic stroke.

Surgical strategy for intracranial endodermal cyst--case report.

Two cases of endodermal cyst of the posterior fossa are reported. A 12-year-old girl presented with severe headache and vomiting caused by increased intracranial pressure. Computed tomography and magnetic resonance (MR) imaging showed a cystic mass occupying the ambient and quadrigeminal cisterns.

[A case of herpetic meningoencephalitis associated with massive intracerebral hemorrhage during acyclovir treatment: a rare complication].

We report a case of a 35-year-old female with herpetic meningoencephalitis confirmed by polymerase chain reaction and immunohistochemical study for herpes simplex virus-1 accompanied with a massive intracerebral hematoma as a complication. A hematoma localized at the medial temporal lobe and the medial frontal lobe occurred on the 11th day after initiation of acyclovir treatment. She subsequently required emergency surgery for temporal lobectomy, as well as hematoma and external decompression.

The course of the lesser petrosal nerve on the middle cranial fossa.

Objective: The course of the lesser petrosal nerve is not well understood and may be confused with the course of the greater petrosal nerve during middle fossa surgery. The objective was to examine the course of the lesser petrosal nerve along the floor of the middle cranial fossa from the region of the geniculate ganglion to its outlet from the skull base. There are no studies focused on the course of this nerve in relationship to the floor of the middle cranial fossa.

[Superior sagittal sinus thrombosis caused by Crohn's disease and macrocytic anemia : a case report].

A 32-years-old man with a past history of hemorrhoids presenting with hemiparesis was diagnosed as having sagittal sinus thrombosis with hemorrtagic infarction. Laboratory data revealed macrocytic anemia (Hb 11.2 g/d/) with hypoproteinernia (5.

Can proximity of the occipital artery to the greater occipital nerve act as a cause of idiopathic greater occipital neuralgia? An anatomical and histological evaluation of the artery-nerve relationship.

Background: The purpose of this study was to clarify whether proximity of the occipital artery to the greater occipital nerve can act as a cause of occipital neuralgia, analogous to the contribution of intracranial vessels due to compression in cranial nerve neuralgias, represented by trigeminal neuralgias due to compression of the trigeminal nerve root by adjacent arterial loops.

Methods: Twenty-four suboccipital areas in cadaver heads were studied for anatomical relationships between the occipital artery and the greater occipital nerve, with histopathological assessment of the greater occipital nerve for signs of mechanical damage.

Results: The occipital artery and greater occipital nerve were found to cross each other in the nuchal subcutaneous layer, and the latter was constantly situated superficial to the former at the cross point.

Anesthetic management of an extremely obese patient.

We present the case of a morbidly obese woman, with a body mass index (BMI) of 73.7 kg.m(-2), who had a gynecological operation under combined general and epidural anesthesia.

Anatomic dissection and classic three-dimensional documentation: a unit of education for neurosurgical anatomy revisited.

Objective And Importance: Despite development of computer-assisted neurosurgical navigation, learning by dissecting anatomic specimens is still important.

Clinical Presentation: We describe the processes from preparation of specimens for cranial dissection to documentation of three-dimensional (3-D) stereoscopic pictures, particularly focusing on the latter, which has been initiated in the Microneuroanatomy Laboratory, Department of Neurological Surgery, University of Florida.

Intervention: Preparation consists of irrigation of the major vessels and injection of colored silicone.

Nevoid Basal cell carcinoma syndrome with medulloblastoma and meningioma--case report.

A 35-year-old man presented with a rare case of nevoid basal cell carcinoma syndrome, or Gorlin's syndrome, associated with both medulloblastoma and meningioma, manifesting as visual field constriction due to multiple parasellar tumors. He had undergone resection of a medulloblastoma at the age of 1 year 9 months, followed by adjunctive irradiation with a total dose of 40 Gy. He presented with multiple subcutaneous nodules on his face and neck.