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gather snails; "We went snailing in the summer"
freshwater or marine or terrestrial gastropod mollusk usually having an external enclosing spiral shell

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1. 脊髄障害の解剖学および局在性 anatomy and localization of spinal cord disorders
2. D型大血管転位の病態生理、臨床症状、および診断 pathophysiology clinical manifestations and diagnosis of d transposition of the great arteries
3. 腰部脊柱管狭窄症：病態生理、臨床的特徴、および診断 lumbar spinal stenosis pathophysiology clinical features and diagnosis
4. 腰部脊柱管狭窄症：治療および予後 lumbar spinal stenosis treatment and prognosis
5. 腰仙部神経根障害：病態生理、臨床的特徴、および診断 lumbosacral radiculopathy pathophysiology clinical features and diagnosis

English Journal

Acetylcholine Promotes Binding of α-Conotoxin MII at α3 β2 Nicotinic Acetylcholine Receptors.

Sambasivarao SV, Roberts J, Bharadwaj VS, Slingsby JG, Rohleder C, Mallory C, Groome JR, McDougal OM, Maupin CM.Author information Chemical and Biological Engineering Department, Colorado School of Mines, 1500 Illinois Street, Golden, CO 80401 (USA).Abstractα-Conotoxin MII (α-CTxMII) is a 16-residue peptide with the sequence GCCSNPVCHLEHSNLC, containing Cys2-Cys8 and Cys3-Cys16 disulfide bonds. This peptide, isolated from the venom of the marine cone snail Conus magus, is a potent and selective antagonist of neuronal nicotinic acetylcholine receptors (nAChRs). To evaluate the impact of channel-ligand interactions on ligand-binding affinity, homology models of the heteropentameric α3 β2 -nAChR were constructed. The models were created in MODELLER with the aid of experimentally characterized structures of the Torpedo marmorata-nAChR (Tm-nAChR, PDB ID: 2BG9) and the Aplysia californica-acetylcholine binding protein (Ac-AChBP, PDB ID: 2BR8) as templates for the α3 - and β2 -subunit isoforms derived from rat neuronal nAChR primary amino acid sequences. Molecular docking calculations were performed with AutoDock to evaluate interactions of the heteropentameric nAChR homology models with the ligands acetylcholine (ACh) and α-CTxMII. The nAChR homology models described here bind ACh with binding energies commensurate with those of previously reported systems, and identify critical interactions that facilitate both ACh and α-CTxMII ligand binding. The docking calculations revealed an increased binding affinity of the α3 β2 -nAChR for α-CTxMII with ACh bound to the receptor, and this was confirmed through two-electrode voltage clamp experiments on oocytes from Xenopus laevis. These findings provide insights into the inhibition and mechanism of electrostatically driven antagonist properties of the α-CTxMIIs on nAChRs.
Chembiochem : a European journal of chemical biology.Chembiochem.2014 Feb 10;15(3):413-24. doi: 10.1002/cbic.201300577. Epub 2014 Jan 13.
α-Conotoxin MII (α-CTxMII) is a 16-residue peptide with the sequence GCCSNPVCHLEHSNLC, containing Cys2-Cys8 and Cys3-Cys16 disulfide bonds. This peptide, isolated from the venom of the marine cone snail Conus magus, is a potent and selective antagonist of neuronal nicotinic acetylcholine receptors
PMID 24420650

From molecular phylogeny towards differentiating pharmacology for NMDA receptor subtypes.

Platt RJ1, Curtice KJ2, Twede VD1, Watkins M1, Gruszczyński P3, Bulaj G4, Horvath MP1, Olivera BM1.Author information 1Department of Biology, University of Utah, Salt Lake City, Utah 84112.2Department of Biology, University of Utah, Salt Lake City, Utah 84112. Electronic address: kigen.curtice@utah.edu.3Medicinal Chemistry, University of Utah, Salt Lake City, Utah 84112; Intercollegiate Faculty of Biotechnology and Chemistry, University of Gdańsk, 80-952 Gdańsk, Poland; Intercollegiate Faculty of Biotechnology and Chemistry, Medical University of Gdańsk, 80-822 Gdańsk, Poland.4Medicinal Chemistry, University of Utah, Salt Lake City, Utah 84112.AbstractIn order to decode the roles that N-methyl-D-aspartate (NMDA) receptors play in excitatory neurotransmission, synaptic plasticity, and neuropathologies, there is need for ligands that differ in their subtype selectivity. The conantokin family of Conus peptides is the only group of peptidic natural products known to target NMDA receptors. Using a search that was guided by phylogeny, we identified new conantokins from the marine snail Conus bocki that complement the current repertoire of NMDA receptor pharmacology. Channel currents measured in Xenopus oocytes demonstrate conantokins conBk-A, conBk-B, and conBk-C have highest potencies for NR2D containing receptors, in contrast to previously characterized conantokins that preferentially block NR2B containing NMDA receptors. Conantokins are rich in γ-carboxyglutamate, typically 17-34 residues, and adopt helical structure in a calcium-dependent manner. As judged by CD spectroscopy, conBk-C adopts significant helical structure in a calcium ion-dependent manner, while calcium, on its own, appears insufficient to stabilize helical conformations of conBk-A or conBk-B. Molecular dynamics simulations help explain the differences in calcium-stabilized structures. Two-dimensional NMR spectroscopy shows that the 9-residue conBk-B is relatively unstructured but forms a helix in the presence of TFE and calcium ions that is similar to other conantokin structures. These newly discovered conantokins hold promise that further exploration of small peptidic antagonists will lead to a set of pharmacological tools that can be used to characterize the role of NMDA receptors in nervous system function and disease.
Toxicon : official journal of the International Society on Toxinology.Toxicon.2014 Feb 6. pii: S0041-0101(14)00037-3. doi: 10.1016/j.toxicon.2014.01.016. [Epub ahead of print]
In order to decode the roles that N-methyl-D-aspartate (NMDA) receptors play in excitatory neurotransmission, synaptic plasticity, and neuropathologies, there is need for ligands that differ in their subtype selectivity. The conantokin family of Conus peptides is the only group of peptidic natural p
PMID 24508768

A disulfide tether stabilizes the block of sodium channels by the conotoxin μO{section}-GVIIJ.

Gajewiak J, Azam L, Imperial J, Walewska A, Green BR, Bandyopadhyay PK, Raghuraman S, Ueberheide B, Bern M, Zhou HM, Minassian NA, Hagan RH, Flinspach M, Liu Y, Bulaj G, Wickenden AD, Olivera BM, Yoshikami D, Zhang MM.Author information Department of Biology and Department of Medicinal Chemistry, L. S. Skaggs Pharmacy Institute, University of Utah, Salt Lake City, UT 84112.AbstractA cone snail venom peptide, μO§-conotoxin GVIIJ from Conus geographus, has a unique posttranslational modification, S-cysteinylated cysteine, which makes possible formation of a covalent tether of peptide to its target Na channels at a distinct ligand-binding site. μO§-conotoxin GVIIJ is a 35-aa peptide, with 7 cysteine residues; six of the cysteines form 3 disulfide cross-links, and one (Cys24) is S-cysteinylated. Due to limited availability of native GVIIJ, we primarily used a synthetic analog whose Cys24 was S-glutathionylated (abbreviated GVIIJSSG). The peptide-channel complex is stabilized by a disulfide tether between Cys24 of the peptide and Cys910 of rat (r) NaV1.2. A mutant channel of rNaV1.2 lacking a cysteine near the pore loop of domain II (C910L), was >103-fold less sensitive to GVIIJSSG than was wild-type rNaV1.2. In contrast, although rNaV1.5 was >104-fold less sensitive to GVIIJSSG than NaV1.2, an rNaV1.5 mutant with a cysteine in the homologous location, rNaV1.5[L869C], was >103-fold more sensitive than wild-type rNaV1.5. The susceptibility of rNaV1.2 to GVIIJSSG was significantly altered by treating the channels with thiol-oxidizing or disulfide-reducing agents. Furthermore, coexpression of rNaVβ2 or rNaVβ4, but not that of rNaVβ1 or rNaVβ3, protected rNaV1.1 to -1.7 (excluding NaV1.5) against block by GVIIJSSG. Thus, GVIIJ-related peptides may serve as probes for both the redox state of extracellular cysteines and for assessing which NaVβ- and NaVα-subunits are present in native neurons.
Proceedings of the National Academy of Sciences of the United States of America.Proc Natl Acad Sci U S A.2014 Feb 4. [Epub ahead of print]
A cone snail venom peptide, μO§-conotoxin GVIIJ from Conus geographus, has a unique posttranslational modification, S-cysteinylated cysteine, which makes possible formation of a covalent tether of peptide to its target Na channels at a distinct ligand-binding site. μO§-conotoxin GVIIJ is a 35-aa
PMID 24497506

Japanese Journal

イモガイの最危険種アンボイナガイの毒のヒトに対する致死量

吉葉繁雄
日本衛生学雑誌 39(2), 565-572, 1984
… Conus-sting, 55 cases, including 21 fatalities caused by about 20 species of Conus … is therefore considered to be the most dangerous snail belonging to the genus Conus. … These values represent the lowest value of venoms in various species of Conus …
NAID 130001001030

イモガイ刺症特にアンボイナガイ刺症対策としての緊ばくの効果

吉葉繁雄
日本衛生学雑誌 39(2), 555-564, 1984
… Conus-sting is a syndrome produced by the sting of marine snails belonging to the genus Conus. … The radular tooth, which is hollow and harpoon-like in shape and charged with venom, is ejected from the tip of a tapering proboscis lengthened from the mouth (rostrum). More than 55 cases of Conus-sting including 21 fatalities have been recorded in tropical Indo-Pacific (16 cases including 7 fatalities in Japan) as of Aug. 1982. …
NAID 130001001029

イモガイ類の毒物, Kohn, A. J., Saunders, P. R. and Wiener, S., 1960, Preliminary studies on the venom of the marine snail Conus. nn. New York Acad. Sci., 90(3), 706-725