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991.

Background  

Stromal signalling increases the lateral cell adhesions of prostate epithelial cells grown in 3D culture. The aim of this study was to use microarray analysis to identify significant epithelial signalling pathways and genes in this process.  相似文献   
992.
Hizikia fusiforme is a commonly used food that possesses potent anti-bacterial, anti-fungal, and anti-inflammatory activities. The immunostimulatory activities of aqueous extract of Hizikia fusiforme (HFAE) in RAW 264.7 macrophages and whole spleen cells were investigated. HFAE activated RAW 264.7 macrophages to produce cytokines such as nitric oxide (NO), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in a dose-dependent manner. In addition, HFAE induced the mRNA expression of TNF-α, IL-1β, and IL-6 in RAW 264.7 macrophages. Moreover, HFAE stimulated proliferation of whole spleen cells and reference mitogen. Taken together, the results demonstrate that HFAE potently activates the immune function by regulating NO, TNF-α, IL-1β, and IL-6 in RAW 264.7 macrophage and promoting spleen cell proliferation.  相似文献   
993.
994.
He X  Lv R  Wang K  Huang X  Wu W  Yin L  Liu Y 《The protein journal》2011,30(7):437-446
Cytoglobin, generated using genetic engineering method, is a kind of recombinant human stellate cell activation-associated protein. We speculate that it could influence the development of hepatic fibrosis like Sellate cell activation-associated protein which was discovered by Kawada et al. Therefore, we investigated its anti-fibrosis effect on liver both in vivo and in vitro. During our research, we found that cytoglobin showed obvious effect compared with the control group on Thioacetamide-induced liver fibrosis in SD rats, including significantly decrease in aspartate aminotransferase, Hyaluronic acid, laminin and collagen I(Col I) levels in serum and hydroxyproline in livers, which are the important indices reflecting the degree of hepatic fibrosis. Meanwhile, the viability of rat hepatic stellate cell line T6 (HSC-T6) cells was inhibited by cytoglobin and the apoptosis induced by cytoglobin in HSC-T6 cells was detected by Annexin V/PI double staining. Activation of the caspase cascade including caspase-3 for the intrinsic pathways was demonstrated. The results also showed that the expression of Bcl-2 protein decreased whereas that of Bax protein increased, leading to an increase of the Bax/Bcl-2 ratio. Our results demonstrated that cytoglobin exhibited anti-fibrosis activity on livers in vivo and in vitro, involving apoptosis induction.  相似文献   
995.
996.
To investigate the biological significance of ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) involvement in oocyte maturation, we screened for proteins that bound to UCH-L1 in mouse ovaries, and we found that the prostate tumor overexpressed-1 (PTOV1) protein was able to bind to UCH-L1. PTOV1 is highly expressed in prostate cancers and considered as a potential marker for carcinogenesis and the progress of prostate cancer. It was reported that PTOV1 plays an important role in cell cycle regulation, but its role in mammalian oocyte development and meiosis is still unclear. In this paper, it was found that the expression levels of PTOV1 in mouse ovaries progressively increased from prepubescence to adulthood. And we found by immunohistochemistry that PTOV1 spreaded in both the cytoplasm and nuclei of oocytes during prepuberty, but in normal adult mouse oocytes, it concentrated not only in nuclei but also on the plasma membrane, though in some oocytes with abnormal shapes, PTOV1 did not display the typical distribution patterns. In granulosa cells, however, it was found to locate in the cytoplasm at all the selected ages. In postnatal mouse ovaries (28 days), estradiol treatment induced the adult-specific distribution pattern of PTOV1 in oocytes. In addition, UCH-L1 was shown to be associated with CDK1, which participated in the regulation of cell cycle and oocyte maturation. Therefore, we propose that the distribution changes of PTOV1 are age-dependent, and significant for mouse oocyte development and maturation. Moreover, the discovery that PTOV1 is associated with UCH-L1 in mouse oocytes supports the explanations for that UCH-L1 is involved in oocyte development and maturation, especially under the regulation of estrogen.  相似文献   
997.
The production of extracellular pullulanase by Bacillus licheniformis NRC22 was investigated using different fermentation modes. In batch culture maximal enzyme activity of 18 U/ml was obtained after 24 h of growth. In continuous fermentation by the free cells, maximal reactor productivity (4.15 KU/l/h) with enzyme concentration of 14.8 U/ml and specific productivity of 334.9 U/g wet cells/h was attained at a dilution rate of 0.28/h, over a period of 25 days. B. licheniformis NRC22 cells were immobilized on Ca-alginate. The immobilization conditions with respect to matrix concentration and cell load was optimized for maximal enzyme production. In repeated batch operation, the activity of the immobilized cells was stable during the 10 cycles and the activity remained between 9.8 and 7.7 U/ml. Continuous production of pullulanase by the immobilized cells was investigated in a packed–bed reactor. Maximal reactor productivity (7.0 KU/h) with enzyme concentration of 16.8 U/ml and specific productivity of 131.64 U/g wet cells/h was attained at dilution rate of 0.42/h. The enzyme activity in the effluent started to decline gradually to the level of 8.7 U/ml after 25 days of the operation.  相似文献   
998.
Tyrosinase is a key enzyme in the biosynthesis of melanin, and the use of inhibitors against tyrosinase can prevent hyperpigmentation by inhibiting enzymatic oxidation. However, the current use of tyrosine inhibitors is limited by their low activities and high toxicities. The aim of the present research was to develop novel whitening agents, or tyrosinase-targeted medicine, from a submerged culture of the fungus Ganoderma lucidum. Methyl lucidenate F was isolated from the ethanol-soluble-acidic components (ESACs) of G. lucidum, with the structure of ESACs elucidated via UV, LC-MS, and 13C-NMR spectral analysis. The tyrosinase inhibitory activity was measured using catechol as a substrate. Methyl lucidenate F displayed uncompetitive inhibition of the potato tyrosinase activity, for which Lineweaver-Burk plots revealed a maximum reaction rate (V max) of 0.4367/min, Michaelis constant (K m) of 6.765 mM and uncompetitive inhibition constant (K i) of 19.22 μM. Meanwhile, methyl lucidenate F (tetra cyclic triterpenoid) exhibited high tyrosinase inhibitory activity, with an IC50 of 32.23 μM. These results suggest that methyl lucidenate F may serve as a potential candidate for skin-whitening agents.  相似文献   
999.
Transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt) provide economic, environmental and health benefits by maintaining or increasing crop yields with fewer applications of insecticide. To sustain these benefits, it is important to delay the evolution of insect resistance to the proteins, and to ensure that the proteins do not harm non-target organisms, particularly those that may control secondary pests that would otherwise flourish because of reduced insecticide applications. Vip3A is a Bt vegetative insecticidal protein that is active against lepidopterous pests. It has a different mode of action from other proteins for control of Lepidoptera in current Bt crops, and when combined with these proteins, it should help to delay the evolution of pest resistance to Bt crops. This paper presents data on the effects of Vip3A on non-target organisms, and an ecological risk assessment of MIR162 maize, which expresses Vip3Aa20. Laboratory studies indicate few adverse effects of Vip3A to non-target organisms: 11 of 12 species tested showed no adverse effects when exposed to high concentrations of Vip3A relative to estimated exposures resulting from cultivation of MIR162 maize. Daphnia magna exposed to Vip3Aa20 were unaffected in terms of survival or fecundity, but grew slightly more slowly than unexposed controls. The data indicate that cultivation of MIR162 maize poses negligible risk to non-target organisms, and that crops producing Vip3A are unlikely to adversely affect biological control organisms such that benefits from reduced insecticide applications are lost.  相似文献   
1000.
The Brazilian Atlantic Forest is a Biodiversity Hotspot, yet many biological groups in this biome are poorly known. We compiled information on the diversity of Atlantic Forest tiger moths (Arctiidae) and assessed the resemblance among localities, whether arctiid assemblages are concordant with major vegetation types, and the importance of environmental factors in structuring the variation among assemblages. Additionally, we developed a procedure composed of subsampling and procrustean analysis to assess the robustness of the results from community composition ordinations when localities differ in species richness. To do this, we built a database from specimens deposited in the ten most important Brazilian entomological collections, and mapped species richness in one-degree latitude/longitude grid cells. We employed Principal Coordinates Analysis to assess similarities among the best-sampled localities. We obtained 8,667 records including 1,193 species, representing 60 and 20% of the estimated Brazilian and Neotropical faunas, respectively. Our subsampling procedure indicated that the ordination was not greatly affected by differences in species richness, and was congruent with major vegetation types. Lowland localities on the seacoast were quite distinct in species composition. A second group included localities in montane areas in the southeast part of the biome. The last group included localities in the southern region and those with Araucaria forests, and was associated with long distances from the ocean, even distribution of precipitation throughout the year, and large annual temperature ranges.  相似文献   
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