The effect of extracellular lanthanum on neuromuscular transmission was studied in cockroach leg muscle and larval mealworm ventral muscle by means of microelectrodes. Miniature excitatory postsynaptic potential (MEPSP) frequency was markedly increased after lanthanum was added, in the presence and absence of calcium. The potentiation by La3+ was suppressed in a high Ca2+ saline and enhanced in...

Rare earth element pollution (REEs) and acid rain (AR) pollution simultaneously occur in many regions, which resulted in a new environmental issue, the combined pollution of REEs and AR. The effects of the combined pollution on the antioxidant enzyme system of plant roots have not been reported. Here, the combined effects of lanthanum ion (La3+), one type of REE, and AR on the antioxidant enzym...

a pvc membrane electrode based on 1-[({[(butylsulfunyl)carbothioyl]disulfanyl} carbothioyl)sulfanyl]butane as a suitable ion carrier for determination of lanthanum(iii) ion was prepared. this electrode revealedsuch a good selectivity toward la3+ ion over a wide variety of other metal ions. some experimental parametersuch as membrane composition, nature, and amount of plasticizer, the amount of ...

The molecular mechanisms by which Ca2+ and metal ions interact with the binding sites that modulate the tight junctions (TJs) have not been fully described. Metal ions were used as probes of these sites in the frog urinary bladder. Basolateral Ca2+ withdrawal induces the opening of the TJs, a process that is abruptly terminated when Ca2+ is readmitted, and is followed by a complete recovery of ...

TSH (thyrotropin)-stimulated human thyroid adenylate cyclase has a biphasic response to Ca2+, being activated by submicromolar Ca2+ (optimum 22nM), with inhibition at higher concentrations. Calmodulin antagonists caused an inhibition of TSH-stimulated adenylate cyclase in a dose-dependent manner. Inhibition of TSH-and TSIg-(thyroid-stimulating immunoglobulins)-stimulated activity was more marke...

Cations have generally been reported to prevent jellyfish venom-induced hemolysis through multiple mechanisms by spectrophotometry. Little attention has been paid to the potential interaction between cations and hemoglobin, potentially influencing the antagonistic effect of cations. Here, we explored the effects of five reported cations, La3+, Mn2+, Zn2+, Cu2+ and Fe2+, on a hemolytic test syst...

The binding properties of metal ions to a pectic polysaccharide, rhamnogalacturonan II (RG-II), from plant cell walls were analyzed by size-exclusion HPLC/ICP-MS. The dimeric RG-II borate complex (dRG-II-B) from sugar beet and red wine contained 0.8 - 1.1 mol/mol of B, 0.8 - 1.1 mol/mol of Ca, 0.1 - 0.3 mol/mol of Sr, and 0.03 - 0.07 mol/mol of Ba. The treatment of dRG-II-B with Sr2+, Ba2+, Pb2...

La3+ and Sm3+ - doped Bi2Mn2O7 nanocatalysts were synthesized in 1 M NaOH aqueous solution, via a stoichiometric 1:1 Bi:Mn molar ratio hydrothermal method at 180 °C for 48 h. Bi(NO3)3, MnO2, La(NO3)3 and Sm2O3 were used as raw materials. The synthesized nanomaterials were characterized by powder X-ray diffraction (PXRD) technique. Both of the La3+ and Sm3+ - doped Bi2Mn2O7 nanomaterials were cr...