Photosynthetic characteristics, leaf ionic content, and net fluxes of Na(+), K(+), and Cl(-) were studied in barley (Hordeum vulgare L) plants grown hydroponically at various Na/Ca ratios. Five weeks of moderate (50 mM) or high (100 mM) NaCl stress caused a significant decline in chlorophyll content, chlorophyll fluorescence characteristics, and stomatal conductance (g(s)) in plant leaves grown...

Myofibroblast differentiation is a key process in pathogenesis of fibrotic diseases. Cardiac glycosides (ouabain, digoxin) inhibit Na(+)-K(+)-ATPase, resulting in increased intracellular [Na(+)]-to-[K(+)] ratio in cells. Microarray analysis suggested that increased intracellular [Na(+)]/[K(+)] ratio may promote the expression of cyclooxygenase-2 (COX-2), a critical enzyme in the synthesis of pr...

Calcium influx into cultured retinal amacrine cells is followed by a small, slow, inward current that we show here results from the operation of electrogenic Na-Ca exchange. The activity of the exchanger is shown to correlate with the magnitude of the Ca2+ load and to depend on both the Ca2+ and Na+ gradients. Li+ is unable to substitute for Na+ and in the absence of Na+, slow tail currents are...

We have explored the processes regulating presynaptic calcium concentration ([Ca(2+)](i)) in the generation of post-tetanic potentiation (PTP) at crayfish neuromuscular junctions, using spectrophotometric dyes to measure changes in [Ca(2+)](i) and [Na(+)](i) and effects of inhibitors of Ca(2+)-transport processes. The mitochondrial Na(+)/Ca(2+) exchange inhibitor CGP 37157 was without effect, w...

Since monosodium urate (NaU) may play an important etiologic role in the formation of renal stones containing Ca in patients with hyperuricosuria, the current studies were undertaken to define some of the physiocochemical factors which determine the formation of NaU. In solutions containing Na, uric acid was rapidly transformed to NaU at pH greater than 6. The results indicated that NaU, and no...

Na, K and Cl measurements have been made on frozen sections of chick red blood cells throughout embryonic development, using electron-probe microanalysis. There is an apparent fluctuation in the levels of these elements during maturation, although the Na/K ratio remains fairly constant. The nuclear Na concentration resembles that of the cytoplasm, rather than that of the medium, at all stages. ...

The removal of CO2 through chemical absorption in a bench-scale spray dryer absorber was investigated experimentally using the lime slurry as absorbent. The effect of important operating parameters on CO2 removal efficiency has been investigated; in selected ranges of operating parameters, increasing gas inlet temperature and absorbent concentration lead to permanent efficiency decline, increas...