The presence of Ca (concentration, ca. 0.4 mM) in the growth medium causes cells of Desulfovibrio vulgaris (Hildenborough) to aggregate, leading to a decrease in plating efficiency. When the Ca concentration in the medium was reduced 20-fold, cell aggregation did not occur and the plating efficiency increased from an initial value of 34% to a final value of 56%.

Sucrose is the most cariogenic dietary carbohydrate because it is a substrate for insoluble extracellular polysaccharide (IEPS) production in dental biofilms, which can proportionally decrease bacterial density and, consequently, the number of biofilm calcium (Ca) binding sites. Ca bound to bacterial cell walls can be released into the biofilm fluid during a cariogenic challenge, reducing the d...

The membrane excitability and contraction were examined in single barnacle muscle fibers with different internal Ca(++) concentrations by using buffer solutions made up with EGTA and Ca-gluconate in various proportions. During the passage of dc currents the membrane shows all-or-none spike potentials for internal Ca(++) concentrations below about 8 x 10(-8)M, oscillatory potential changes in th...

The stromal interacting molecule (STIM1) is pivotal for store-operated Ca(2+) entry (SOC). STIM1 proteins sense the Ca(2+) concentration within the lumen of the endoplasmic reticulum (ER) via an EF-hand domain. Dissociation of Ca(2+) from this domain allows fast oligomerization of STIM1 and the formation of spatially discrete clusters close to the plasma membrane. By lifetime-imaging of STIM1 i...

Understanding the mechanisms that regulate xylem transport of calcium (Ca) to snap bean (Phaseolus vulgaris L.) pods could allow approaches to increase pod Ca concentration and enhance the nutritional value of edible pods. Using the snap bean cultivars Hystyle and Labrador, which exhibit high and low pod Ca levels, respectively, we wished to determine whether there were differences between the ...

Seventy Two sediments from four stations (Anzali, Tonekabon, Noshahr and Amirabad), located in Caspian Sea-Iranian coast were examined on the basis of P-fractionation in autumn and winter of 2013-2014. Several forms of the phosphorus in sediment were separated and extracted according to sequential extraction method. Then the extracted phosphorus in each fraction was determined by UV–Vis spectro...

Seventy Two sediments from four stations (Anzali, Tonekabon, Noshahr and Amirabad), located in Caspian Sea-Iranian coast were examined on the basis of P-fractionation in autumn and winter of 2013-2014. Several forms of the phosphorus in sediment were separated and extracted according to sequential extraction method. Then the extracted phosphorus in each fraction was determined by UV–Vis s...

Contraction and relaxation are fundamental aspects of cardiomyocyte functional biology. They reflect the response of the contractile machinery to the systolic increase and diastolic decrease of the cytoplasmic Ca(2+) concentration. The analysis of contractile function and Ca(2+) transients is therefore important to discriminate between myofilament responsiveness and changes in Ca(2+) homeostasi...

The purpose of this study was to investigate the response of physicochemical properties of gerbera (Gerbera Jamesonii L.) to silica nanoparticles (Nanoparticle-SiO2) and calcium chelate (Ca-Chelate) in nutrient solutions. A factorial experiment based on completely randomized design with two factors was conducted in four replicates. The first factor the concentration of Nanoparticle-SiO2 in nutr...