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91.
Madhav Prasad Neupane Il Song Park Tae Sung Bae Ho Keun Yi Fumio Watari Min Ho Lee 《Materials Chemistry and Physics》2012
This study examined the in vitro cell-material interactions on four different types of titanium surfaces: a polished Ti surface, TiO2 nanotube surfaces fabricated in a fluorinated glycerol solution (TN), fluorinated glycerol solution with 1 wt% anionic surfactant sodium dodecyl sulphate (TN-SDS), and fluorinated glycerol solution with 1 wt% cationic surfactant cetyl trimethyl ammonium bromide (TN-CTAB), respectively. The surfaces exhibited distinct surface morphologies and geometrical features. Surface energy calculation shows that TN surface enhances the hydrophilic character by significantly increasing the surface energy. The osteoblast cell growth behavior on the four different surfaces was examined using the MC3T3-E1 cell line for 1 day. When the anodized surfaces were compared for the cell-materials interaction, each of the surfaces showed different properties that affected the cell–material interactions. Proliferation of the cells was noticed with distinctive cell-to-cell attachment on the TN surfaces. Good cellular adhesion with extracellular matrix extensions between the cells was noticed in the TN samples. The TiO2 nanotubes grown in the surfactant-assisted fluorinated electrolyte did not show significant cell growth on the surface and some cell death was observed. The cell adhesion, differentiation and alkaline phosphatase activity were more pronounced on the TN surface. The MTT assays also revealed an increase in living cell density and proliferation on the TN surfaces. Overall, a rough surface morphology and surface energy are important factors for better cell material interactions. 相似文献
92.
Alina Jakób Jolanta BryjakHalina Wójtowicz Viera IlleováJúlius Annus Milan Polakovič 《Food chemistry》2010
Ohmic heating of milk and fruit and vegetable juices was carried out at several incubation temperatures to investigate inactivation of alkaline phosphatase, pectin methylesterase and peroxidase. Mechanisms of inactivation of these enzymes and corresponding kinetic models were verified for each food material, using the multitemperature evaluation of inactivation data. Compared to inactivation by conventional indirect heating, kinetic parameters were changed but inactivation mechanisms remained the same. The kinetic parameter changes were relatively minor for pectin methylesterase and alkaline phosphatase. A significant destabilization of the labile isozyme fraction of peroxidase occurred by the effect of ohmic heating when the greatest decrease of stability was obtained for carrot juice. 相似文献
93.
Nagai N Anzawa T Satoh Y Suzuki T Tajima K Munekata M 《Journal of Bioscience and Bioengineering》2006,101(6):511-514
We investigated the effect of gamma-irradiation on the activities of MC3T3-E1 cells cultured on gamma-irradiated salmon atelocollagen (SAC) scaffolds. SAC-cultured samples were irradiated at doses of 10, 15, and 25 kGy. Gamma-irradiation had a significant impact on the activities of MC3T3-E1 cells. The proliferation rates and alkaline phosphatase activities of MC3T3-E1 cells increased with gamma-irradiation dose. 相似文献
94.
Mills SJ Dozol H Vandeput F Backers K Woodman T Erneux C Spiess B Potter BV 《Chembiochem : a European journal of chemical biology》2006,7(11):1696-1706
3-Hydroxybenzene 1,2,4-trisphosphate 4 is a new myo-inositol 1,4,5-trisphosphate analogue based on the core structure of benzene 1,2,4-trisphosphate 2 with an additional hydroxyl group at position-3, and is the first noninositol based compound to be a substrate for inositol 1,4,5-trisphosphate 5-phosphatase. In physicochemical studies on 2, when three equivalents of protons were added, the (31)P NMR spectrum displayed monophasic behaviour in which phosphate-1 and phosphate-2 behaved independently in most of the studied pH range. For compound 4, phosphate-2 and phosphate-4 interacted with the 3-OH group, which does not titrate at physiological pH, displaying complex biphasic behaviour which demonstrated co-operativity between these groups. Phosphate-1 and phosphate-2 strongly interacted with each other and phosphate-4 experienced repulsion because of the interaction of the 3-OH group. Benzene 1,2,4-trisphosphate 2 is resistant to inositol 1,4,5-trisphosphate type I 5-phosphatase catalysed dephosphorylation. However, surprisingly, 3-hydroxybenzene 1,2,4-trisphosphate 4 was dephosphorylated by this 5-phosphatase to give the symmetrical 2,3-dihydroxybenzene 1,4-bisphosphate 16. The extra hydroxyl group is shown to form a hydrogen bond with the vicinal phosphate groups at -15 degrees C, and (1)H NMR titration of the ring and hydroxyl protons in 4 shows the OH proton to be strongly stabilized as soon as the phosphate groups are deprotonated. The effect of the phenolic 3-OH group in compound 4 confirms a critical role for the 6-OH group of the natural messenger in the dephosphorylation mechanism that persists even in radically modified analogues. 相似文献
95.
WANG Shao-feng HAN Jia-yu FU Xue-qi ZHAO Zhi-zhuang Joe 《Canadian Metallurgical Quarterly》2011,27(3)
PTPRU is an MAM domain-containing receptor-like protein tyrosine phosphatase. Previous studies have demonstrated an important role of the enzyme in the maintenance of epithelial integrity and in the regulation of the Wnt/β-catenin signaling pathway. To better understand the function of PTPRU, we cloned and expressed the intra- cellular portion of PTPRU as a GST fusion protein in E. coli cells. We purified the protein to homogeneity and used it to immunize mice for antibody production. The resultant antibody specifically recognized PTPRU over-expressed in the cell line. Western blot analyses demonstrated the partition of truncated forms of PTPRU containing the cadhe- rin-like domain in the Triton X-100-insoluble fraction, and immunofluorescent cell staining revealed the localization of these proteins in punctate intracellular structures. Our data suggest that the cadhefin-like domain of PTPRU has a major role in determining its intracellular localization. 相似文献
96.
The effects of long‐term atmospheric deposition of pollutant elements on the trans‐surface causative relationships at three lake sites having different catchment characteristics were investigated in this study. The selected determinants included lake productivity, bottom sediment quality, and a suite of microbial variables (microbial biomass (Cmic); basal respiration; substrate‐induced respiration; bacterial:fungal ratio; metabolic quotient; and alkaline phosphatase and FDAase activities) measured at the land–water interface, in relation to atmospheric deposition of phosphate; nitrate; ammonium; sulphate; calcium; and magnesium. The results indicated significant between‐site differences (P < 0.001) in the atmospheric deposition of phosphate (0.21–1.96 kg.h?1.year?1); nitrate (2.77–28.05 kg.h?1.year?1); ammonium (0.58–11.60 kg.h?1.year?1); sulphate (5.64–32.15 kg.h?1.year?1); calcium (4.50–30.00 kg.h?1.year?1); and magnesium (1.50–12.15 kg.h?1.year?1), as well as a consistently increasing input of these ions across time. The catchment vegetation had important effects on microbial variables that, in turn, affected lake productivity. Interfaces of woodland lake were found to be rich in phenolics, supporting low Cmic and activities. Except for alkaline phosphatase, which declined over time, atmospheric deposition of pollutant elements increased the Cmic and activities at the land–water interface. The time lag correlation analysis indicated the Cmic and lake productivity relationships were significantly altered by atmospherically driven nitrogen and phosphorus inputs, with a time lag of 2–3 years. Despite being supportive, aerial nutrient inputs appeared to have a destabilizing effect on both, microbial biomass and lake productivity variables. These observations indicate that if present atmospheric deposition trends of pollutant elements continue, it will modify the cross‐domain causative relationships of inland lentic systems over the long term. These study results are relevant for the formulation of strategies for managing freshwater tropical lakes. 相似文献
97.
98.
Masataka Hirasaki Fumika Nakamura Kazuo Yamagishi Minori Numamoto Yukiko Shimada Keigo Uehashi Shigeru Muta Minetaka Sugiyama Yoshinobu Kaneko Satoru Kuhara Satoshi Harashima 《Journal of Bioscience and Bioengineering》2010,109(5):433-441
Expression profiles of protein phosphatase (PPase) disruptants were analyzed by use of Pearson's correlation coefficient to find profiles that correlated with those of 316 Reference Gene (RG) disruptants harboring deletions in genes with known functions. Twenty-six Δppase disruptants exhibited either a positive or negative correlation with 94 RG disruptants when the p value for Pearson's correlation coefficient was > 0.2. Some of the predictions that arose from this analysis were tested experimentally and several new Δppase phenotypes were found. Notably, Δsit4 and Δsiw14 disruptants exhibited hygromycin B sensitivity, Δsit4 and Δptc1 disruptants grew slowly on glycerol medium, the Δptc1 disruptant was found to be sensitive to calcofluor white and congo red, while the Δppg1 disruptant was found to be sensitive to congo red. Because on-going analysis of expression profiles of Saccharomyces cerevisiae disruptants is rapidly generating new data, we suggest that the approach used in the present study to explore PPase function is also applicable to other genes. 相似文献
99.
用悬浮聚合法制备了直径在0.81~2.83μm胺基磁性微珠;用戊二醛法对ApoB_(100)单抗进行了碱性磷酸醇的标记,并成功地进行了ApoB_(100)蛋白的定量检测。 相似文献
100.
用粉煤灰去除富营养湖中酶污染物的研究 总被引:5,自引:0,他引:5
本文讨论了利用粉煤灰去除富营养型湖泊水体磷酸酶的可行性与适宜条件。结果表明,粉煤灰能有效地去除湖泊表层水和间隙水中的磷酸酶。温度、粉煤灰的用量、灰的粒径对去除率有一定影响。 相似文献