CALHM3 Is Essential for Rapid Ion Channel-Mediated Purinergic Neurotransmission of GPCR-Mediated Tastes

Binding of sweet, umami, and bitter tastants to G protein-coupled receptors (GPCRs) in apical membranes of type II taste bud cells (TBCs) triggers action potentials that activate a voltage-gated nonselective ion channel to release ATP to gustatory nerves mediating taste perception. Although calcium homeostasis modulator 1 (CALHM1) is necessary for ATP release, the molecular identification of the channel complex that provides the conductive ATP-release mechanism suitable for action potential-dependent neurotransmission remains to be determined. Here we show that CALHM3 interacts with CALHM1 as a pore-forming subunit in a CALHM1/CALHM3 hexameric channel, endowing it with fast voltage-activated gating identical to that of the ATP-release channel in vivo. Calhm3 is co-expressed with Calhm1 exclusively in type II TBCs, and its genetic deletion abolishes taste-evoked ATP release from taste buds and GPCR-mediated taste perception. Thus, CALHM3, together with CALHM1, is essential to form the fast voltage-gated ATP-release channel in type II TBCs required for GPCR-mediated tastes. Ma et al. identify a CALHM1/CALHM3 hetero-hexameric ion channel as the mechanism by which type II taste bud cells release ATP as a neurotransmitter to gustatory neurons in response to GPCR-mediated tastes, including sweet, bitter, and umami substances. © 2018 Elsevier Inc

Variety of the Wave Change in Compound Muscle Action Potential in an Animal Model

Study DesignAnimal study.PurposeTo review the present warning point criteria of the compound muscle action potential (CMAP) and investigate new criteria for spinal surgery safety using an animal model.Overview of LiteratureLittle is known about correlation palesis and amplitude of spinal cord monitoring.MethodsAfter laminectomy of the tenth thoracic spinal lamina, 2-140 g force was delivered to the spinal cord with a tension gage to create a bilateral contusion injury. The study morphology change of the CMAP wave and locomotor scale were evaluated for one month.ResultsFour different types of wave morphology changes were observed: no change, amplitude decrease only, morphology change only, and amplitude and morphology change. Amplitude and morphology changed simultaneously and significantly as the injury force increased (p<0.05) Locomotor scale in the amplitude and morphology group worsened more than the other groups.ConclusionsAmplitude and morphology change of the CMAP wave exists and could be the key of the alarm point in CMAP

Transcatheter arterial embolization for intercostal arterio-esophageal fistula in esophageal cancer

Abstract Background While esophageal fistula formation in the adjacent organs is associated with high rates of morbidity and mortality, the management of non-aortic arterio-esophageal fistula has not been frequently reported. Case presentation A 69-year-old Japanese man who had undergone definitive chemoradiotherapy for esophageal cancer was admitted to our hospital with hematemesis. He was diagnosed with mediastinal abscess caused by esophageal perforation, and esophageal bypass surgery was performed. After 3 days, he presented with fatal hemoptysis. As angiography revealed an intercostal artery pseudoaneurysm, transcatheter arterial embolization was performed. Conclusions When patients with esophageal cancer, especially those with a history of radiotherapy and/or mediastinitis, present with hematemesis and/or hemoptysis, the possibility of non-aortic arterio-esophageal fistula should be considered. Transcatheter arterial embolization is an effective treatment for non-aortic arterio-esophageal fistula

Differences in Demographic and Radiographic Characteristics between Patients with Visible and Invisible T1 Slopes on Lateral Cervical Radiographic Images

Introduction: The T1 slope is important for cervical surgical planning, and it may be invisible on radiographic images. The prevalence of T1 invisible cases and the differences in demographic and radiographic characteristics between patients whose T1 slopes are visible or invisible remains unexplored. Methods: This pilot study aimed to evaluate the differences in these characteristics between outpatients whose T1 slopes were visible or invisible on radiographic images. Patients (n = 60) who underwent cervical radiography, whose T1 slope was confirmed clearly, were divided into the visible (V) group and invisible (I) group. The following radiographic parameters were measured: (1) C2-7 sagittal vertical axis (SVA), (2) C2-7 angle in neutral, flexion, and extension positions. Results: Based on the T1 slope visibility, 46.7% of patients were included in group I. The I group had significantly larger C2-7 SVA than the V group for males (p p = 0.362). Discussion: The mean C2-7 angle in neutral and flexion positions was not significantly different between the V and I groups for either sex. The mean C2-7 angle in the extension position was greater in the V group. The T1 slope was invisible in males with high C2-7 SVA

Posterior fusion of the occipital axis in children with upper cervical disorder using both C2 pedicle and laminar screws (C2 hybrid screws)

Introduction: An occipital-cervical surgery for children is challenging for surgeons because of the immature bone quality, extensive anatomical variability, and small osseous structures. Furthermore, occipital-C2 fusion in children results in great stress on the C2 screws. We report a technique that uses both C2 pedicle and bilateral lateral mass screws (C2 hybrid screws) in children with an upper cervical disorder to preserve motion segment and secure strength in those who require occipital-cervical fusion. Case Report: Case 1 was that of a 5-year-old girl with Down syndrome who had atlantoaxial dislocation and os odontoideum. Owing to the C1 hypoplasia, the posterior arch was fractured by the C1 lateral mass screw. Therefore, O-C2 fusion was performed. C2 bilateral lamina screws were added along with the C2 bilateral pedicle screws for reinforcement. Case 2 was that of an 8-year-old boy who presented with torticollis and neck pain. The patient was diagnosed as having atlantoaxial rotatory fixation. The right vertebral artery was obstructed, and the left vertebral artery was dominant. The C1 posterior arch was bifid and assimilated with the occipital bone. C2 bilateral lamina screws were added with the right C2 pedicle screw for reinforcement. Both cases attained bone union after O-C2 fusion surgery using hybrid screws. Conclusions: The use of C2 hybrid screws with both C2 pedicle and bilateral lateral mass screws can preserve mobile segments in the fusion area in young children who require occipital-cervical fixation