Search results for "EGTA"
showing 10 items of 35 documents
The spasmogenic effects of vanadate in human isolated bronchus
1997
1. Inhalation of vanadium compounds, particularly vanadate, is a cause of occupational bronchial asthma. We have now studied the action of vanadate on human isolated bronchus. Vanadate (0.1 microM-3 mM) produced concentration-dependent, well-sustained contraction. Its -logEC50 was 3.74 +/- 0.05 (mean +/- s.e.mean) and its maximal effect was equivalent to 97.5 +/- 4.2% of the response to acetylcholine (ACh, 1 mM). 2. Vanadate (200 microM)-induced contraction of human bronchus was epithelium-independent and was not inhibited by indomethacin (2.8 microM), zileuton (10 microM), a mixture of atropine, mepyramine and phentolamine (each at 1 microM), or by mast cell degranulation with compound 48/…
Early signaling network in tobacco cells elicited with methyl jasmonate and cyclodextrins.
2012
We analyze, for the first time, the early signal transduction pathways triggered by methyl jasmonate (MJ) and cyclodextrins (CDs) in tobacco (Nicotiana tabacum) cell cultures, paying particular attention to changes in cytosolic free Ca(2+) concentration ([Ca(2+)](cyt)), the production of hydrogen peroxide (H(2)O(2)) and nitric oxide (NO), and late events like the induction of capsidiol. Our data indicate that MJ and CDs trigger a [Ca(2+)](cyt) rise promoted by Ca(2+) influx through Ca(2+)-permeable channels. The joint presence of MJ and CDs provokes a first increase in [Ca(2+)](cyt) similar to that observed in MJ-treated cells, followed by a second peak similar to that found in the presence…
The Efficacy of an Experimental Single Solution versus Alternate Use of Multiple Irrigants on Root Dentin Microhardness
2013
The objective of this work was to use fnite element analysis to compare the effect of forces coming to bear on abutments 4.1 or 5.0 mm in diameter connThis study was carried-out to evaluate and compare the efficacy of various irrigants when used singly or in combination on the microhardness of root canal dentin. Study Design: A total of 50 root-halves were randomly divided into 5 groups immediately after the initial baseline microhardness measurements and treated with: Group-1; 7.5%Ethylenediaminetetraaceticacid (EDTA)+ 2.5%sodium hypochlorite (NaOCl), Group-2; 7.5%ethyleneglycol-bis[b-aminoethylether]-N, N,N0,N0-tetraaceticacid (EGTA)+ 2.5%NaOCl, Group-3; 7.5%trans1,2diaminocyclohexane NNN…
Sequestering ability of polyaminopolycarboxylic ligands towards dioxouranium(VI) cation
2006
Abstract In the present paper, some results of an investigation (at t = 25 °C by potentiometry, ISE-H+ glass electrode) on the sequestering ability of five different polyaminopolycarboxylic ligands [Nitrilotriacetate (NTA), ethylenediamine-N,N,N′,N′-tetraacetate (EDTA), ethylene glycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetate (EGTA), diethylenetriamine-N,N,N′,N″,N″-pentaacetate (DTPA), triethylenetetraamine-N,N,N′,N″,N′′′,N′′′-hexaacetate (TTHA)] towards dioxouranium(VI) cation in sodium chloride aqueous solutions, at I = 0.7 mol L−1 are reported. Calculations performed on potentiometric data gave evidence of the formation of the following species (log β in parenthesis): UO2(NTA)H0 (12…
Aizliegtās vienošanās publiskajos iepirkumos.
2019
Darba mērķis ir izpētīt aizliegtās vienošanās publiskajos iepirkumos Latvijā, kā arī Eiropas Savienībā, vērtēt citu dalībvalstu pieredzi un izvirzīt priekšlikumus likumdošanas pilnveidošanai, lai izskaustu aizliegtas vienošanās publiskajos iepirkumos. Darbs sastāv no ievada, trīs nodaļām, kurām ir septiņas apakšnodaļas, kopsavilkuma ar secinājumiem un priekšlikumiem, trīs anotācijām un izmantotās literatūras saraksta. Aizliegtu vienošanos slēgšana publiskajos iepirkumos, arvien ir aktuāla problēma. Autorei, pildot savus darba pienākumus, ir nācies saskarties ar gadījumiem, kad acīmredzami starp pretendentiem pastāv aizliegta vienošanās, tādēļ autore šo tēmu izvēlējās kā maģistra darba tēmu.…
Eksperimenta nozīme pētnieciskajā žurnālistikā: "Aizliegtā paņēmiena" gadījums
2018
Bakalaura darba tēma ir “Eksperimenta nozīme pētnieciskajā žurnālistikā. “Aizliegtā paņēmiena” gadījums”. Darba mērķis ir noskaidrot eksperimenta un slēptās novērošanas lomu un ētiskumu žurnālistikas raidījumā televīzijā, kā arī analizēt problēmas, kas saistāmas ar to lietojumu un meklēt tām risinājumu. Bakalaura darba teorētiskā pieeja ir mediju ētikas studijas, kā arī žurnālistu profesionālās identitātes teorija. Analizēti tiek divi raidījuma eksperimenti, kuros piedalījusies arī bakalaura darba autore - operācijas “Tokija” un “Zīdaiņu aukle”. Pētījuma veikšanai izmantotas gadījuma studijas, kuru ietvaros, savukārt, pašnovērojums un mediju, ētikas ekspertu, un raidījuma galvenā redaktora …
Comparison of the contractile effects of endothelin-1 and sarafotoxin S6b in goat isolated cerebral arteries
1992
1. The effects of endothelium-derived endothelin-1 and snake venom-derived sarafotoxin S6b, peptides with striking structural and functional similarities, were examined and compared in isolated middle cerebral arteries of goats. 2. Endothelin-1 and sarafotoxin S6b contracted cerebral arteries in a concentration-dependent manner. The potency of endothelin-1 (EC50 = 4.9 (3.9-6.2) x 10(-10) M) was about ten times higher than that of sarafotoxin S6b (EC50 = 5.5 (4.4-6.9) x 10(-9) M). The tension returned to basal values after repeated washings and contraction with endothelin-1 could be reproduced. Endothelin-1 and sarafotoxin S6b induced further contraction in arteries precontracted with prosta…
Effects of Mn2+ on the responses induced by different spasmogens in the oestrogen-primed rat uterus
1997
Abstract We investigated the effect of Mn 2+ on the mechanical responses evoked by high K + (60 mM) or low Na + (25 mM) solutions, oxytocin and neurokinin A in the oestrogen-primed rat uterus. In a Ca 2+ -free, Mn 2+ (0.54 mM)-containing solution, high K + or low Na + solutions produced contractions of smaller amplitude than those observed in a normal Ca 2+ (0.54 mM) solution, which were abolished by nifedipine (1 μM). Oxytocin (1 μM) and neurokinin A (1 μM, in the presence of phosphoramidon 1 μM) evoked nifedipine-insensitive contractile responses similar to (oxytocin) or smaller (neurokinin A) in amplitude than those observed in Ca 2+ (0.54 mM)-containing solution. In strips loaded with C…
Ca2+ entry blockers inhibit prostaglandin F2 alpha-induced cerebrovascular contractile responses in goats.
1991
We examined the effects of extracellular Ca2+ withdrawal and of Ca2+ entry blockers on goat cerebrovascular responses to prostaglandin F2 alpha (PGF2 alpha). We measured isometric tension in isolated middle cerebral arteries, and cerebral blood flow (CBF) in unanesthetized animals. PGF2 alpha produced concentration-dependent contractions of isolated arteries. The contractions were partially inhibited by incubation in Ca(2+)-free medium (by 63.1 +/- 1.8% without ethyleneglycol-bis-(beta-amino-ethylether)-N,N,N',N'-tetra-a cetate (EGTA), and by 82.4 +/- 3.7% with EGTA). The Ca2+ entry blockers inhibited PGF2 alpha-elicited contraction and relaxed PGF2 alpha-precontracted arteries (nicardipine…
Calcium Dependence of the Mechanical Response Evoked by Okadaic Acid in Smooth Muscle
1995
The effects of okadaic acid (OA), obtained from a culture of the marine dinoflagellate Prorocentrum Lima were studied on isolated strips of rat myometrium. The contractile response evoked by OA at 5, 10, and 20 μM in normal physiological solution was unaffected in the presence of tetrodotoxin (10 μM), indomethacin (3 μM), or a cocktail of antagonists which blocked muscarinic, adrenergic, histaminergic, serotonergic, and opioid receptors. Similarly, the response to OA was unaffected in the presence of nifedipine at a concentration (1 μM) which completely or highly blocked the response to KCl (60 mM), oxytocin (1 μM), or acetylcholine (100 μM). In a Ca 2+ -free 1 mM EGTA-containing solution, …