We examined liquid crystalline phases of the cytoskeletal polyelectrolyte filamentous (F-)actin in the presence of multivalent counterions. As a function of increasing ion concentration, the F-actin rods in either an isotropic or a nematic phase will transform into a new and unexpected lamellar phase of cross-linked rafts (L(XR) phase), before condensing into a bundled phase of parallel, close-...

The mechanism ofthe Bat+-induced contraction was investigated using intact and saponin-treated skinned smooth muscle (skinned muscle) strips of the rabbit mesenteric artery . After depletion of Ca21 stored in the caffeinesensitive site, >0 .65 mM Ba2+ evoked contraction in muscle strips depolarized with 128 mM K+ in Cat+-free solution in a dose-dependent fashion, and the ED50 values for Ca2' an...

The mechanism ofthe Bat+-induced contraction was investigated using intact and saponin-treated skinned smooth muscle (skinned muscle) strips of the rabbit mesenteric artery . After depletion of Ca21 stored in the caffeinesensitive site, >0 .65 mM Ba2+ evoked contraction in muscle strips depolarized with 128 mM K+ in Cat+-free solution in a dose-dependent fashion, and the ED50 values for Ca2' an...

The photoluminescence properties of Eu2+-activated α’-Sr2SiO4 and α’-Ba2SiO4 with a high Eu2+ concentration were investigated. In the case of Sr2−xEuxSiO4, emission was shifted from 585 to 611 nm with increasing the total Eu2+ concentration (x) from 0.1 to 0.8. This trend was similar to that in Ba2−xEuxSiO4, where the emission was shifted from 513 to 545 nm. The large redshifts in both the exci...

Recent evidence indicates that ionic selectivity in voltage-gated Na+ channels is mediated by a small number of residues in P-region segments that link transmembrane elements S5 and S6 in each of four homologous domains denoted I, II, III, and IV. Important determinants for this function appear to be a set of conserved charged residues in the first three homologous domains, Asp(I), Glu(II), and...

Present work studies the influence of pretreatment milling media (deionized water (BLTOS-H) and isopropanol (BLTOS-i)) on surface characteristics, structure, chemical composition catalytic activity non-stoichiometric Ba2Sr2La2Ti4O12 perovskites. The IR spectroscopy XRD analyses shows a difference in structure phase two materials. X-ray photoelectron detects Ba2+- La3+-enriched Sr2+-depleted sur...

Voltage-dependent calcium channels (VDCCs) play an essential role in regulating cerebral artery diameter and it is widely appreciated that the L-type VDCC, CaV1.2, encoded by the CACNA1C gene, is a principal Ca2+ entry pathway in vascular myocytes. However, electrophysiological studies using 10 mM extracellular barium ([Ba2+]o) as a charge carrier have shown that ~20% of VDCC currents in cerebr...

Fertilization of the sea urchin egg is accompanied by the assembly of an extracellular glycoprotein coat, the fertilization membrane. Assembly of the fertilization membrane involves exocytosis of egg cortical granules, divalent cation-mediated association of exudate proteins with the egg glycocalyx (the vitelline layer), and cross-linking of the assembled structure by ovoperoxidase, a fertiliza...

GABAC responses were recorded in cultured cone-driven horizontal cells from the catfish retina using the patch clamp technique. At a holding potential of -49 mV, a bicuculline-resistant inward current (IGABA) was observed when 10 microM GABA was applied. The amplitude of IGABA increased as the extracellular Ca2+ ([Ca2+]o) was increased. Concentration-response curves of IGABA at 2.5 and 10 mM -C...