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Article ; Online: Use of 2-octyl cyanoacrylate for wound closure in a modified Roberts-Bistner procedure for eyelid agenesis in five cats (nine eyes).

Reed, Zoe / Doering, Clinton J / Barrett, Paul M

Journal of the American Veterinary Medical Association

2018 Volume 252, Issue 2, Page(s) 215–221

Abstract: CASE DESCRIPTION 5 cats (9 eyes) were evaluated for surgical correction of bilateral eyelid agenesis. CLINICAL FINDINGS All eyes lacked > 25% of the temporal upper eyelid, and all cats had clinical signs attributable to chronic ocular exposure. ... ...

Abstract	CASE DESCRIPTION 5 cats (9 eyes) were evaluated for surgical correction of bilateral eyelid agenesis. CLINICAL FINDINGS All eyes lacked > 25% of the temporal upper eyelid, and all cats had clinical signs attributable to chronic ocular exposure. Abnormalities were limited to the ocular surface in the 4 female cats, whereas the sole male cat had additional abnormalities consistent with anterior segment dysgenesis. TREATMENT AND OUTCOME A modified Roberts-Bistner procedure involving 2-octyl cyanoacrylate (2OCA) was performed on 9 eyes; 1 eye was enucleated. Surgical wounds in the initial 3 eyes were closed with 2OCA plus sutures, and flaps were lined with conjunctiva. The technique was optimized for remaining eyes by use of a single suture for flap apposition, no conjunctival lining of flaps, and 2OCA alone for wound closure. Median duration of surgery was 35 minutes/eye for the initial 3 eyes versus 16 minutes/eye for the subsequent 6 eyes treated with the optimized procedure. After surgery, all cats had complete palpebral reflexes and resolution of clinical signs of ocular irritation. Minor complications in the early postoperative period included eyelid swelling (n = 9), poor cosmesis (7), and persistent epiphora (3). By the second recheck examination, swelling had resolved and cosmesis was considered excellent. Two eyes with epiphora had been treated with the initial modified procedure and required cryoepilation for resolution of epiphora. CLINICAL RELEVANCE The modified Roberts-Bistner procedure for eyelid agenesis involving 2OCA for wound closure provided functional, cosmetic eyelids that improved comfort and provided protection of the ocular surface in affected cats.
MeSH term(s)	Animals ; Cat Diseases/congenital ; Cat Diseases/surgery ; Cats ; Cyanoacrylates/pharmacology ; Eyelids/abnormalities ; Female ; Male ; Surgical Flaps ; Suture Techniques ; Tissue Adhesives/pharmacology ; Wound Healing
Chemical Substances	Cyanoacrylates ; Tissue Adhesives ; octyl 2-cyanoacrylate (6C655P1XVG)
Language	English
Publishing date	2018-01-10
Publishing country	United States
Document type	Journal Article
ZDB-ID	390811-2
ISSN	1943-569X ; 0003-1488
ISSN (online)	1943-569X
ISSN	0003-1488
DOI	10.2460/javma.252.2.215
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Article: Use of 2-octyl cyanoacrylate for wound closure in a modified Roberts-Bistner procedure for eyelid agenesis in five cats (nine eyes)

Reed, Zoe / Clinton J. Doering / Paul M. Barrett

Journal of the American Veterinary Medical Association. 2018 Jan. 15, v. 252, no. 2

2018

Abstract	CASE DESCRIPTION 5 cats (9 eyes) were evaluated for surgical correction of bilateral eyelid agenesis. CLINICAL FINDINGS All eyes lacked > 25% of the temporal upper eyelid, and all cats had clinical signs attributable to chronic ocular exposure. Abnormalities were limited to the ocular surface in the 4 female cats, whereas the sole male cat had additional abnormalities consistent with anterior segment dysgenesis. TREATMENT AND OUTCOME A modified Roberts-Bistner procedure involving 2-octyl cyanoacrylate (2OCA) was performed on 9 eyes; 1 eye was enucleated. Surgical wounds in the initial 3 eyes were closed with 2OCA plus sutures, and flaps were lined with conjunctiva. The technique was optimized for remaining eyes by use of a single suture for flap apposition, no conjunctival lining of flaps, and 2OCA alone for wound closure. Median duration of surgery was 35 minutes/eye for the initial 3 eyes versus 16 minutes/eye for the subsequent 6 eyes treated with the optimized procedure. After surgery, all cats had complete palpebral reflexes and resolution of clinical signs of ocular irritation. Minor complications in the early postoperative period included eyelid swelling (n = 9), poor cosmesis (7), and persistent epiphora (3). By the second recheck examination, swelling had resolved and cosmesis was considered excellent. Two eyes with epiphora had been treated with the initial modified procedure and required cryoepilation for resolution of epiphora. CLINICAL RELEVANCE The modified Roberts-Bistner procedure for eyelid agenesis involving 2OCA for wound closure provided functional, cosmetic eyelids that improved comfort and provided protection of the ocular surface in affected cats.
Keywords	cats ; conjunctiva ; eyelids ; females ; males ; reflexes ; surgery ; sutures
Language	English
Dates of publication	2018-0115
Size	p. 215-221.
Publishing place	American Veterinary Medical Association
Document type	Article
ZDB-ID	390811-2
ISSN	1943-569X ; 0003-1488
ISSN (online)	1943-569X
ISSN	0003-1488
DOI	10.2460/javma.252.2.215
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Article ; Online: Effects of intramuscular injection of glycopyrrolate on Schirmer tear test I results in dogs.

Doering, Clinton J / Lukasik, Victoria M / Merideth, Reuben E

Journal of the American Veterinary Medical Association

2016 Volume 248, Issue 11, Page(s) 1262–1266

Abstract: OBJECTIVE To determine effects of glycopyrrolate administered IM on Schirmer tear test I (STT I) measurements in dogs. DESIGN Prospective clinical study. ANIMALS 13 client- and staff-owned dogs. PROCEDURES For both eyes of each dog, STT I measurements ... ...

Abstract	OBJECTIVE To determine effects of glycopyrrolate administered IM on Schirmer tear test I (STT I) measurements in dogs. DESIGN Prospective clinical study. ANIMALS 13 client- and staff-owned dogs. PROCEDURES For both eyes of each dog, STT I measurements were recorded twice 20 minutes apart (at T1 and T2) and 2 to 4 hours later (at T3). Glycopyrrolate (0.01 mg/kg [0.005 mg/lb]) was administered IM to all dogs (3 dogs received an injection of saline [0.9% NaCl] solution on an earlier occasion), and final STT I measurements were recorded 20 minutes later (at T4). Intraocular pressures, heart rate, and respiratory rate were also recorded at each time point. RESULTS Ophthalmic variables did not differ between right and left eyes. In all dogs, variables at T1, T2, or T3 (measurements before glycopyrrolate administration) did not differ; baseline values were therefore defined at T3. At T4, STT I measurements were significantly decreased (mean ± SD decrease, 67.4 ± 15.4% [mean actual decrease, 15.8 mm/min]). During the same period, mean heart rate increased by 26.5 ± 12.0% (mean actual increase, 30.2 beats/min). Glycopyrrolate had no effect on intraocular pressure or respiratory rate. In 5 dogs at 24 hours after glycopyrrolate treatment, STT I measurement in each eye had returned to baseline value. Saline solution treatment (3 dogs) had no effect on any variables. CONCLUSIONS AND CLINICAL RELEVANCE In dogs, IM injection of glycopyrrolate resulted in a clinically relevant transient decrease in aqueous tear production. Application of lacrimomimetics beginning at the time of or within 20 minutes after glycopyrrolate premedication is recommended until STT I measurements return to baseline.
MeSH term(s)	Animals ; Dogs/physiology ; Glycopyrrolate/administration & dosage ; Glycopyrrolate/pharmacology ; Injections, Intramuscular/veterinary ; Lacrimal Apparatus/drug effects ; Prospective Studies ; Tears/drug effects ; Tears/secretion
Chemical Substances	Glycopyrrolate (V92SO9WP2I)
Language	English
Publishing date	2016-06-01
Publishing country	United States
Document type	Journal Article
ZDB-ID	390811-2
ISSN	1943-569X ; 0003-1488
ISSN (online)	1943-569X
ISSN	0003-1488
DOI	10.2460/javma.248.11.1262
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Zs.A 423: Show issues

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Article ; Online: Mathematical Discrepancies of the Tono-Pen Applanation Tonometer.

Doering, Clinton J / Feldman, Eugenia / Bdolah-Abram, Tali / Merideth, Reuben E / Ofri, Ron

Journal of glaucoma

2016 Volume 26, Issue 2, Page(s) e30–e36

Abstract: Purpose of the study: The purpose of the study was to determine if Tono-Pen tonometers use simple average and coefficient of variation (CV) algorithms to calculate intraocular pressure (IOP).: Material and methods: IOPs were measured as part of ... ...

Abstract	Purpose of the study: The purpose of the study was to determine if Tono-Pen tonometers use simple average and coefficient of variation (CV) algorithms to calculate intraocular pressure (IOP). Material and methods: IOPs were measured as part of routine ocular examination in 152 client-owned dogs. Using 11 Tono-Pen's, a total of 778 averaged readings were collected. Individual IOP readings, and average IOP and CV displayed by the instrument, were recorded. Average IOP and CV were then manually calculated from individual readings and compared with those displayed by the instrument. Results: The mean absolute difference between the calculated and displayed average IOP was 1.37±2.01 mm Hg (P<0.001). In 6% of cases, the calculated average IOP was 5 to 15 mm Hg different from the displayed average IOP. The difference between the displayed and calculated average IOP was significantly higher in hypertensive eyes with displayed IOP≥25 mm Hg. Calculated CV was equal to, lower than, or greater than displayed CV in 28.6%, 1.5%, and 69.7% of cases, respectively. In 17.6% of cases, calculated CV was >20%, but displayed CV was <5%. Receiver operating characteristic analysis could not correlate number of individual IOP readings with magnitude of difference in average IOP. Conclusions: Calculated average IOP and CV differ significantly from values displayed by the instrument, especially at higher IOPs. A difference of ≥5 mm Hg between calculated and displayed average IOP seen in 6% of cases may impact clinical judgement. Displayed CV<5% does not correlate with accurate IOP measurement based on individual results.
MeSH term(s)	Algorithms ; Animals ; Dogs ; Female ; Intraocular Pressure/physiology ; Male ; Ocular Hypertension/diagnosis ; Ocular Hypertension/veterinary ; Predictive Value of Tests ; ROC Curve ; Reproducibility of Results ; Statistics as Topic/standards ; Tonometry, Ocular/standards ; Tonometry, Ocular/veterinary
Language	English
Publishing date	2016-08-31
Publishing country	United States
Document type	Journal Article
ZDB-ID	913494-3
ISSN	1536-481X ; 1057-0829
ISSN (online)	1536-481X
ISSN	1057-0829
DOI	10.1097/IJG.0000000000000524
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Zs.A 3795: Show issues

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Article: Molecular pharmacology of non-L-type calcium channels.

Doering, Clinton J / Zamponi, Gerald W

Current pharmaceutical design

2004 Volume 11, Issue 15, Page(s) 1887–1898

Abstract: Voltage-gated calcium channels are key sources of calcium entry into the cytosol. Mutations in calcium channels have been implicated in numerous disorders such as migraine, incomplete congenital X-linked stationary night blindness, epilepsy, and ataxia, ... ...

Abstract	Voltage-gated calcium channels are key sources of calcium entry into the cytosol. Mutations in calcium channels have been implicated in numerous disorders such as migraine, incomplete congenital X-linked stationary night blindness, epilepsy, and ataxia, and they are important therapeutic targets for the treatment of pain, stroke, hypertension, and epilepsy. Calcium channel antagonists can be broadly classified into three groups. 1) Inorganic ions typically nonselectively block the pore of most calcium channel subtypes, and in some cases, alter gating kinetics. 2) Peptides isolated from arachnids, cone snails, and snakes frequently selectively antagonize individual calcium channel subtypes by direct occlusion of the pore or altering gating kinetics. 3) Small organic molecules of various structure-activity-relationship (SAR) classes can mediate both selective and nonselective effects on individual calcium channel subtypes, and occlude the pore or reduce channel availability. Here, we provide an overview of classes of inhibitors of non-L-type calcium channels.
MeSH term(s)	Animals ; Calcium/metabolism ; Calcium Channel Blockers/chemistry ; Calcium Channel Blockers/pharmacology ; Calcium Channels/classification ; Calcium Channels/physiology ; Cytosol/drug effects ; Cytosol/metabolism ; Humans
Chemical Substances	Calcium Channel Blockers ; Calcium Channels ; Calcium (SY7Q814VUP)
Language	English
Publishing date	2004-05-27
Publishing country	United Arab Emirates
Document type	Journal Article ; Research Support, Non-U.S. Gov't ; Review
ZDB-ID	1304236-1
ISSN	1873-4286 ; 1381-6128
ISSN (online)	1873-4286
ISSN	1381-6128
DOI	10.2174/1381612054021042
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Zs.A 4714: Show issues

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Article: Molecular pharmacology of high voltage-activated calcium channels.

Doering, Clinton J / Zamponi, Gerald W

Journal of bioenergetics and biomembranes

2004 Volume 35, Issue 6, Page(s) 491–505

Abstract: Voltage-gated calcium channels are key sources of calcium entry into the cytosol of many excitable tissues. A number of different types of calcium channels have been identified and shown to mediate specialized cellular functions. Because of their ... ...

Abstract	Voltage-gated calcium channels are key sources of calcium entry into the cytosol of many excitable tissues. A number of different types of calcium channels have been identified and shown to mediate specialized cellular functions. Because of their fundamental nature, they are important targets for therapeutic intervention in disorders such as hypertension, pain, stroke, and epilepsy. Calcium channel antagonists fall into one of the following three groups: small inorganic ions, large peptide blockers, and small organic molecules. Inorganic ions nonselectively inhibit calcium entry by physical pore occlusion and are of little therapeutic value. Calcium-channel-blocking peptides isolated from various predatory animals such as spiders and cone snails are often highly selective blockers of individual types of calcium channels, either by preventing calcium flux through the pore or by antagonizing channel activation. There are many structure-activity-relation classes of small organic molecules that interact with various sites on the calcium channel protein, with actions ranging from selective high affinity block to relatively nondiscriminatory action on multiple calcium channel isoforms. Detailed interactions with the calcium channel protein are well understood for the dihydropyridine and phenylalkylamine drug classes, whereas we are only beginning to understand the molecular actions of some of the more recently discovered calcium channel blockers. Here, we provide a comprehensive review of pharmacology of high voltage-activated calcium channels.
MeSH term(s)	Amino Acid Sequence ; Animals ; Calcium/metabolism ; Calcium Channel Blockers/chemistry ; Calcium Channel Blockers/classification ; Calcium Channel Blockers/pharmacology ; Calcium Channels/chemistry ; Calcium Channels/physiology ; Calcium Signaling/physiology ; Cell Membrane Permeability/drug effects ; Cell Membrane Permeability/physiology ; Dihydropyridines/pharmacology ; Humans ; Ion Channel Gating/drug effects ; Ion Channel Gating/physiology ; Membrane Potentials/drug effects ; Membrane Potentials/physiology ; Molecular Sequence Data ; Peptides/pharmacology ; Phenethylamines/pharmacology ; Piperidines/pharmacology ; Porosity ; Structure-Activity Relationship ; Toxins, Biological/pharmacology
Chemical Substances	Calcium Channel Blockers ; Calcium Channels ; Dihydropyridines ; Peptides ; Phenethylamines ; Piperidines ; Toxins, Biological ; Calcium (SY7Q814VUP)
Language	English
Publishing date	2004-06-28
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't ; Review
ZDB-ID	198499-8
ISSN	1573-6881 ; 0145-479X ; 0449-5705
ISSN (online)	1573-6881
ISSN	0145-479X ; 0449-5705
DOI	10.1023/b:jobb.0000008022.50702.1a
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Zs.A 1005: Show issues

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Article ; Online: The Ca(v)1.4 calcium channel: more than meets the eye.

Doering, Clinton J / Peloquin, Jean B / McRory, John E

Channels (Austin, Tex.)

2007 Volume 1, Issue 1, Page(s) 3–10

Abstract: Ca(v)1.4 channels are the latest calcium channels to be described in the literature. Originally identified in 1997 from the human genome project, several reports have since been published describing mutations in the CACNA1F gene encoding Ca(v)1.4 ... ...

Abstract	Ca(v)1.4 channels are the latest calcium channels to be described in the literature. Originally identified in 1997 from the human genome project, several reports have since been published describing mutations in the CACNA1F gene encoding Ca(v)1.4 channels, and implicated these mutations in human disorders such as X-linked cone rod dystrophy (CORDX3) and incomplete X-linked congenital stationary night blindness type 2 (CSNB2). The gene was subsequently cloned and expressed in heterologous expression systems beginning in 2003, and many of the mutations linked to CSNB2 have been tested. Here, we review literature describing the discovery of the CACNA1F gene, its tissue expression profile, alternative splicing events, and biophysical and pharmacological characteristics of the channel in various expression systems. Channel biophysics are also compared to those obtained from recordings made from vertebrate photoreceptors, suggesting that these studies may have been describing Ca(v)1.4 channels in native cells.
MeSH term(s)	Animals ; Calcium Channels, L-Type/genetics ; Calcium Channels, L-Type/metabolism ; Eye Proteins/genetics ; Eye Proteins/metabolism ; Gene Expression Regulation/genetics ; Genetic Diseases, X-Linked/genetics ; Genetic Diseases, X-Linked/metabolism ; Human Genome Project ; Humans ; Mutation ; Night Blindness/genetics ; Night Blindness/metabolism ; Organ Specificity/genetics ; Photoreceptor Cells, Vertebrate/metabolism ; Retinitis Pigmentosa/genetics ; Retinitis Pigmentosa/metabolism
Chemical Substances	CACNA1F protein, human ; Calcium Channels, L-Type ; Eye Proteins
Language	English
Publishing date	2007-01
Publishing country	United States
Document type	Journal Article ; Review
ISSN	1933-6969
ISSN (online)	1933-6969
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Article ; Online: Comparison of arterial and venous whole blood clot initiation, formation, and strength by thromboelastography in anesthetized swine.

Doering, Clinton J / Wagg, Catherine R / Caulkett, Nigel A / McAllister, Russell K / Brookfield, Caroline E / Paterson, Jessica M / Warren, Amy L / Smith, Barbara L / Boysen, Søren R

Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis

2014 Volume 25, Issue 1, Page(s) 20–24

Abstract: Thromboelastography (TEG) analysis was used to determine if differences exist between venous and arterial samples in anesthetized swine, using identical sampling techniques for each of the samples. We hypothesized that TEG parameters would not differ ... ...

Abstract	Thromboelastography (TEG) analysis was used to determine if differences exist between venous and arterial samples in anesthetized swine, using identical sampling techniques for each of the samples. We hypothesized that TEG parameters would not differ between native whole blood venous and arterial samples. Thirty male Landrace swines were included in the study. Both the femoral artery and vein were catheterized using standard cut-down techniques and with identically sized catheters to rule out any catheter size effects on the results. Standard TEG parameters for native whole venous and arterial blood samples (r, K, α, MA, G, and coagulation index) were measured or calculated, and t-test or Mann-Whitney rank-sum test used for comparison when appropriate. Significant differences were detected for r (venous < arterial), K (venous < arterial), α (venous > arterial), and coagulation index (venous > arterial) TEG parameters. No significant differences were measured for MA or G. These differences are important, especially when temporal changes in TEG are utilized to monitor patient stability and fluid therapy protocols using trends in coagulation properties. Taken together, these results suggest that clots are more likely to form at a faster rate in venous samples compared to arterial samples, but the overall clot strength does not differ. Therefore, if TEG analysis is being used to monitor coagulation profiles in a patient, care should be taken to use the same site and technique if results are to be used for comparative purposes.
MeSH term(s)	Animals ; Arteries ; Blood Coagulation/physiology ; Male ; Swine ; Thrombelastography/methods ; Thrombosis/blood ; Veins
Language	English
Publishing date	2014-01
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	1033551-1
ISSN	1473-5733 ; 0957-5235
ISSN (online)	1473-5733
ISSN	0957-5235
DOI	10.1097/MBC.0b013e328364672a
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Zs.A 2920: Show issues

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Article: Cav1.4 encodes a calcium channel with low open probability and unitary conductance.

Doering, Clinton J / Hamid, Jawed / Simms, Brett / McRory, John E / Zamponi, Gerald W

Biophysical journal

2005 Volume 89, Issue 5, Page(s) 3042–3048

Abstract: When transiently expressed in tsA-201 cells, Ca(v)1.4 calcium channels support only modest whole-cell currents with unusually slow voltage-dependent inactivation kinetics. To examine the basis for this unique behavior we used cell-attached patch single- ... ...

Abstract	When transiently expressed in tsA-201 cells, Ca(v)1.4 calcium channels support only modest whole-cell currents with unusually slow voltage-dependent inactivation kinetics. To examine the basis for this unique behavior we used cell-attached patch single-channel recordings using 100 mM external barium as the charge carrier to determine the single-channel properties of Ca(v)1.4 and to compare them to those of the Ca(v)1.2. Ca(v)1.4 channel openings occurred infrequently and were of brief duration. Moreover, openings occurred throughout the duration of the test depolarization, indicating that the slow inactivation kinetics observed at the whole-cell level are caused by sustained channel activity. Ca(v)1.4 and Ca(v)1.2 channels displayed similar latencies to first opening. Because of the rare occurrence of events, the probability of opening could not be precisely determined but was estimated to be <0.015 over a voltage range of -20 to +20 mV. The single-channel conductance of Ca(v)1.4 channels was approximately 4 pS compared with approximately 20 pS for Ca(v)1.2 under the same experimental conditions. Additionally, in the absence of divalent cations, Ca(v)1.4 channels pass cesium ions with a single-channel conductance of approximately 21 pS. Although Ca(v)1.2 opening events were best described kinetically with two open time constants, Ca(v)1.4 open times were best described by a single time constant. BayK8644 slightly enhanced the single-channel conductance in addition to increasing the open time constant for Ca(v)1.4 channels by approximately 45% without, however, causing the appearance of an additional slower gating mode. Overall, our data indicate that single Ca(v)1.4 channels support only minute amounts of calcium entry, suggesting that large numbers of these channels are needed to allow for significant whole-cell current activity, and providing a mechanism to reduce noise in the visual system.
MeSH term(s)	Amino Acid Sequence ; Animals ; Biophysics/methods ; Calcium Channels/chemistry ; Calcium Channels, L-Type/chemistry ; Cell Line, Tumor ; Cloning, Molecular ; DNA/chemistry ; DNA, Complementary/metabolism ; Electrophysiology ; Glutamic Acid/chemistry ; Humans ; Kinetics ; Molecular Sequence Data ; Probability ; Protein Structure, Tertiary ; RNA/chemistry ; Rats ; Sequence Homology, Amino Acid ; Time Factors ; Transfection
Chemical Substances	CACNA1F protein, human ; Calcium Channels ; Calcium Channels, L-Type ; DNA, Complementary ; L-type calcium channel alpha(1C) ; Glutamic Acid (3KX376GY7L) ; RNA (63231-63-0) ; DNA (9007-49-2)
Language	English
Publishing date	2005-11
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	218078-9
ISSN	1542-0086 ; 0006-3495
ISSN (online)	1542-0086
ISSN	0006-3495
DOI	10.1529/biophysj.105.067124
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Zs.A 235: Show issues			Location: Je nach Verfügbarkeit (siehe Angabe bei Bestand) bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular Jg. 1995 - 2021: Lesesall (1.OG) ab Jg. 2022: Lesesaal (EG)
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Article: Scanning mutagenesis of omega-atracotoxin-Hv1a reveals a spatially restricted epitope that confers selective activity against insect calcium channels.

Tedford, Hugo W / Gilles, Nicolas / Ménez, André / Doering, Clinton J / Zamponi, Gerald W / King, Glenn F

The Journal of biological chemistry

2004 Volume 279, Issue 42, Page(s) 44133–44140

Abstract: We constructed a complete panel of alanine mutants of the insect-specific calcium channel blocker omega-atracotoxin-Hv1a. Lethality assays using these mutant toxins identified three spatially contiguous residues, Pro10, Asn27, and Arg35, that are ... ...

Abstract	We constructed a complete panel of alanine mutants of the insect-specific calcium channel blocker omega-atracotoxin-Hv1a. Lethality assays using these mutant toxins identified three spatially contiguous residues, Pro10, Asn27, and Arg35, that are critical for insecticidal activity against flies (Musca domestica) and crickets (Acheta domestica). Competitive binding assays using radiolabeled omega-atracotoxin-Hv1a and neuronal membranes prepared from the heads of American cockroaches (Periplaneta americana) confirmed the importance of these three residues for binding of the toxin to target calcium channels presumably expressed in the insect membranes. At concentrations up to 10 microm, omega-atracotoxin-Hv1a had no effect on heterologously expressed rat Cav2.1, Cav2.2, and Cav1.2 calcium channels, consistent with the previously reported insect selectivity of the toxin. 30 microm omega-atracotoxin-Hv1a inhibited rat Cav currents by 10-34%, depending on the channel subtype, and this low level of inhibition was essentially unchanged when Asn27 and Arg35, which appears to be critical for interaction of the toxin with insect Cav channels, were both mutated to alanine. We propose that the spatially contiguous epitope formed by Pro10, Asn27, and Arg35 confers specific binding to insect Cav channels and is largely responsible for the remarkable phyletic selectivity of omega-atracotoxin-Hv1a. This epitope provides a structural template for rational design of chemical insecticides that selectively target insect Cav channels.
MeSH term(s)	Amino Acid Substitution ; Animals ; Calcium Channel Blockers/pharmacology ; Calcium Channels/immunology ; Cockroaches ; Gryllidae ; Houseflies ; Mutagenesis, Site-Directed ; Protein Conformation ; Rats ; Spider Venoms/genetics ; Spider Venoms/immunology ; Spiders
Chemical Substances	Calcium Channel Blockers ; Calcium Channels ; Spider Venoms ; omega-atracotoxin-HV1
Language	English
Publishing date	2004-08-11
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, U.S. Gov't, Non-P.H.S. ; Research Support, U.S. Gov't, P.H.S.
ZDB-ID	2997-x
ISSN	1083-351X ; 0021-9258
ISSN (online)	1083-351X
ISSN	0021-9258
DOI	10.1074/jbc.M404006200
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In stock of ZB MED Cologne/Königswinter

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