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Reduction Test (reduction + test)
Selected AbstractsAntimicrobial efficiency of titanium dioxide-coated surfacesJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2010P. Muranyi Abstract Aims:, Development and evaluation of an antimicrobially active titanium dioxide coating. Methods and results:, For this purpose, titanium dioxide coatings were applied to glass slides by using a sol-gel method and then exposed to a light source. The antimicrobial efficiency was determined by a count reduction test for selected test strains (Aspergillus niger, Bacillus atrophaeus, Kocuria rhizophila), which were homogenously sprayed onto surface. The bacterial count of K. rhizophila was reduced by up to 3·3 log10 on titanium dioxide samples within 4 h of UV-A light exposure. Experiments with spore formers did not lead to any significant log reduction. A further aspect of this work was to evaluate the effect of selected parameters (relative humidity, inoculation density, radiation intensity) on the antimicrobial efficiency to gain knowledge for further optimization procedures. At a high relative humidity (85% r.h.), increased inactivation was observed for K. rhizophila (up to 5·2 log10). Furthermore, a dependency of the antimicrobial effect on the radiation intensity and the inoculation density was identified. Conclusions:, Antimicrobial surfaces and coatings based on titanium dioxide have the potential to effectively inactivate vegetative micro-organisms. Significance and impact of the study:, Knowledge about the antimicrobial efficiency of titanium dioxide was gained. This is a prerequisite for industrial applications to improve hygiene, food quality and safety. [source] Better Correction of Metabolic Acidosis, Blood Pressure Control, and Phagocytosis with Bicarbonate Compared to Lactate Solution in Acute Peritoneal DialysisARTIFICIAL ORGANS, Issue 2 2001Visith Thongboonkerd Abstract: Lactate solution has been the standard dialysate fluid for a long time. However, it tends to convert back into lactic acid in poor tissue-perfusion states. The aim of this study was to evaluate the efficacy of magnesium (Mg)- and calcium (Ca)-free bicarbonate solution compared with lactate solution in acute peritoneal dialysis (PD). Renal failure patients who were indicated for dialysis and needed acute PD were classified as shock and nonshock groups, and then were randomized to receive either bicarbonate or lactate solution. Twenty patients were enrolled in this study (5 in each subgroup). In the shock group, there were more rapid improvements and significantly higher levels of blood pH (7.40 ± 0.04 versus 7.28 ± 0.05, p < 0.05), serum bicarbonate (23.30 ± 1.46 versus 18.37 ± 1.25 mmol/L, p < 0.05), systolic pressure (106.80 ± 3.68 versus 97.44 ± 3.94 mm Hg, p < 0.05), mean arterial pressure (80.72 ± 2.01 versus 73.28 ± 2.41 mm Hg, p < 0.05), percentages of phagocytosis of circulating leukocytes (65.85%± 2.22 versus 52.12%± 2.71, p < 0.05), and percentages of positive nitroblue tetrazolium (NBT) reduction test without and with stimulation (14.43 ± 1.93 versus 9.43 ± 2.12, p < 0.05 and 65.08 ± 6.80 versus 50.23 ± 4.21, p < 0.05, respectively) in the bicarbonate subgroup compared with the lactate subgroup. In the nonshock group, blood pH, serum bicarbonate, and phagocytosis assays in both subgroups were comparable. Lactic acidosis was more rapidly recovered and was significantly lower with bicarbonate solution for both shock and nonshock groups (3.63 ± 0.37 versus 5.21 ± 0.30 mmol/L, p < 0.05 and 2.92 ± 0.40 versus 3.44 ± 0.34 mmol/L, p < 0.05, respectively). Peritoneal urea and creatinine clearances in both subgroups were comparable for both shock and nonshock groups. There was no peritonitis observed during the study. Serum Mg and Ca levels in the bicarbonate subgroup were significantly lower, but no clinical and electrocardiographic abnormality were observed. We concluded that Mg- and Ca-free bicarbonate solution could be safely used and had better outcomes in correction of metabolic acidosis, blood pressure control, and nonspecific systemic host defense with comparable efficacy when compared to lactate solution. It should be the dialysate of choice for acute PD especially in the poor tissue-perfusion states such as shock, lactic acidosis, and multiple organ failure. [source] Wogonin induces the granulocytic differentiation of human NB4 promyelocytic leukemia cells and up-regulates phospholipid scramblase 1 gene expressionCANCER SCIENCE, Issue 4 2008Kun Zhang Previous studies have firmly demonstrated that wogonin, a naturally occurring monoflavonoid extracted from the root of the Chinese herb medicine Scutellaria baicalensis, could effectively inhibit the proliferation of several cancer cell lines. However, little is known about the effect of wogonin on differentiation induction of leukemic cells. Here we investigate the potential role of wogonin in the proliferation and differentiation of NB4, a human promyelocytic leukemia cell line derived from a patient with acute promyelocytic leukemia. Our results indicated that wogonin significantly suppressed the proliferation and efficiently induced the differentiation of NB4 cells. NB4 cell growth was inhibited by 55,60% after treatment with 50 µM wogonin for a period of 5 days. The results of the nitroblue tetrazolium (NBT) reduction test (with 67.13% positive cells by 50 µM wogonin for 5 days), Giemsa staining (with 67.24% positive cells by 50 µM wogonin for 5 days), and the expression of mature-related cell-surface differentiation antigens CD11b and CD14 (with 70.94% CD11b+ and 5.82% CD14+ cells by 50 µM wogonin for 5 days) demonstrated an increase in the differentiation-inducing action of wogonin on the NB4 cells, which was accompanied by an increase in mRNA and protein expression of phospholipids scramblase 1 (PLSCR1). Meanwhile, the level of phosphorylated PKC, (Ser643) was dramatically increased in wogonin treated NB4 cells. Interestingly, wogonin treatment displayed little effect on the apoptosis of NB4 cells. Taken together, the results reported here demonstrated that wogonin could promote the granulocytic differentiation of NB4 cells by up-regulating the expression of PLSCR1 gene. (Cancer Sci 2008; 99: 689,695) [source] Evaluation of the Limiting Regime in Iron Ore Fines Reduction with H2 -Rich Gases in Fluidized Beds: Fe2O3 to Fe3O4CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 3 2009J. Sturn Abstract In metallurgical processes, fluidized-bed technology is gaining more importance because of its advantages. Processes with H2 -rich and CO-rich reducing gases were developed for the reduction of iron ore fines (e.g. FINEX®). For improvement of these new technologies, greater knowledge about the chemical kinetics of iron ore reduction in fluidized beds is necessary. The scope of this work is to evaluate the limiting regime of the iron ore fines reduction. Therefore, experimental results of reduction tests were compared with theoretically investigated reduction rates. These reduction rates were based on a limitation either of mass transfer through the external gas film to the particle surface, diffusion in a porous product layer (pore diffusion and Knudsen diffusion), diffusion in a dense product layer (solid diffusion) or the phase boundary reaction. The phase boundary reaction was found to be the most likely limiting reaction regime. [source] | ||||||||||