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921.
In this study, we focused on the relationship between aldosterone and NOX1 expression in vascular smooth muscle cells (VSMCs). For the first time, with the use of specific inhibitors of protein kinase C (PKC), we report that PKCδ mediates upregulation of NOX1 induced by 10 nM aldosterone in cultured VSMCs. Participation of PKC in the mediation of NOX1 regulation was further confirmed by the effect of diacylglycerol, a PKC agonist, on the NOX1 RNA in A7r5 cells with Northern blot analysis. To establish cause and effect, we next silenced the PKCδ gene partly by RNA interference and found knockdown of PKCδ gene attenuated aldosterone-induced NOX1 expression, generation of superoxide, as well as protein synthesis in VSMCs. Taken together, these data indicated PKCδ might mediate aldosterone-dependent NOX1 upregulation in VSMCs. In addition, we showed that the cascade from aldosterone to PKCδ activation had the participation of the mineralocorticoid receptor.  相似文献   
922.
We describe here a simple and efficient system of soybean (Glycine max L. Merrill) regeneration through direct somatic embryogenesis by using immature embryonic shoot tips (IEST) as explants. The cultivar Kaohsiung 10 (cv. K10) used in this study did not show embryogenic response either from mature seed-derived explants (cotyledon, embryonic tip, leaf, shoot and root) or immature cotyledons. However, it showed a high percentage (55.8%) of somatic embryo (SEm) formation from the IEST excised 2–3 wk after flowering, thus indicating the crucial roles of type and age of explants. The IEST put forth primary SEm after 2 mo of culturing on Murashige and Skoog (MS) medium supplemented with 6% sucrose, 164.8 μM 2,4-dichlorophenoxyacetic acid (2,4-D), 5 mM asparagine and 684 μM glutamine. Subsequently, secondary SEm were developed 1 mo after culturing on MS medium containing 123.6 μM 2,4-D and 3% sucrose. Cotyledonary embryos were induced on MS medium supplemented with 0.5% activated charcoal after 1 mo. The embryos were desiccated for 72–96 h on sterile Petri dishes and regenerated on hormone-free MS medium. Plantlets with well-developed shoots and roots were obtained within 5–6 mo of culturing of IEST. The SEm-derived plants were morphologically normal and fertile. Various parameters thought to be responsible for efficient regeneration of soybean through somatic embryogenesis are discussed. To our knowledge, this is the first report to employ IEST as explants for successful direct somatic embryogenesis in soybean.  相似文献   
923.

Background  

An elevated plasma glucose concentration has been considered to be a potential risk factor in the pathogenesis of left-displaced abomasums (DA). Therefore the present study was performed to investigate if spontaneous disease (parturient paresis, metritis, ketosis etc) in dairy cows results in elevated concentrations of glucose and cortisol in blood as cortisol is the major regulator of glucose in ruminants.  相似文献   
924.
The Aurora kinases play a critical role in mitosis and have been suggested as promising targets for cancer therapy due to their frequent overexpression in a variety of tumors. Compared with established inhibitors of cell division such as the anti-tubulins, novel agents target mitotic enzymes and show similar efficacy but with fewer side effects. Several small-molecule inhibitors of Aurora kinases have been developed as anticancer agents, some of which have progressed to early clinical evaluation. Here we identified 3-hydroxyflavone as a novel Aurora B inhibitor through high throughput screening. 3-Hydroxyflavone showed potent inhibition to Aurora B with the IC50 on a nanomolar basis in the enzyme-based kinase activity assay. In the cell-based western blotting analysis, 3-hydroxyflavone dramatically decreased the phosphorylation level of Histone H3 on the site of serine 10, demonstrating the potent endogenous Aurora B activity inhibition in cell level. The followed cell image analysis provided the consist result. To make it clear whether 3-hydroxyflavone inhibited Aurora B by direct binding or not, SPR analysis was carried out to measure the affinity of interaction between Aurora B protein and 3-hydroxyflavone and the result proved the binding with high affinity. Usually Aurora activity suppression induced cancer cell proliferation inhibition. Colony formation and cell viability with/without treatment of 3-hydroxyflavone were measured using CCK-8. The growth suppression under 3-hydroxyflavone present and the growth recovery after being released gave strong evidence that presence of 3-hydroxyflavone efficiently inhibited the fast growth of cancer cells.  相似文献   
925.
Glycosaminoglycans (GAGs) like chondroitin sulfate (CS) and heparan sulfate (HS) are synthesized on the tetrasaccharide linkage region, GlcAβ1-3Galβ1-3Galβ1-4Xylβ1-O-Ser, of proteoglycans. The Xyl can be modified by 2-O-phosphate in both CS and HS, whereas the Gal residues can be sulfated at C-4 and/or C-6 in CS but not in HS. To study the roles of these modifications, monoclonal antibodies were developed against linkage glycopeptides of shark cartilage CS proteoglycans, and one was characterized in detail. This antibody bound hexa- and pentasaccharide-peptides more strongly than unsaturated tetrasaccharide-peptides with the unnatural fourth sugar residue (unsaturated hexuronic acid), suggesting the importance of the fifth and/or fourth saccharide residue GalNAc-5 and/or GlcA-4. Its reactivity was not affected by treatment with chondro-4-sulfatase or alkaline phosphatase, suggesting that 4-O-sulfate on the Gal residues and 2-O-phosphate on the Xyl residue were not recognized. Treatment with weak alkali to cleave the Xyl-Ser linkage completely abolished the binding activity, suggesting the importance of the peptide moiety of the hexasaccharide-peptide for the binding. Based on the amino acid composition and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analyses, it was revealed that the peptide moiety is composed of four amino acids, Ser, Pro, Gly, and Glu. Furthermore, the antibody stained wild-type CHO cells significantly, but much weakly mutant cells deficient in xylosyl- or galactosyltransferase-I required for the biosynthesis of the linkage region. These results suggest that the antibody recognizes the structure GalNAc(±6-O-sulfate)-GlcA-Gal-Gal-Xyl-Ser-(Pro, Gly, Glu). The antibody will be a useful tool for investigating the significance of the linkage region in the biosynthesis and/or intracellular transport of different GAG chains especially since such tools to study the linkage region are lacking.  相似文献   
926.
Hydroxycinnamates including p-coumaric acid, caffeic acid, ferulic acid, sinapic acid, and their esterified/etherified conjugates such as chlorogenic acids are abundant in cereals, coffee, fruit and vegetables. Studies have shown their potential in the prevention of chronic diseases such as cardiovascular disease and cancer. The impact of these dietary hydroxycinnamates on health depends on their bioavailability. In this article, in vivo and in vitro studies pertaining to bioavailability of hydroxycinnamates are reviewed and discussed. The chemical structures, existing forms, and/or doses of hydroxycinnamates may affect their metabolic fate. Limited studies suggest that the relative bioavailability of hydroxycinnamates may be in the following order: chlorogenic acid < rosmarinic acid < caffeic acid < ferulic acid < p-coumaric acid. Bound hydroxycinnamates generally have lower bioavailability than their monomer counterparts. Further pharmacokinetic and phamacodynamic studies are required to characterize the metabolism of hydroxycinnamates and their potential health impact in humans.  相似文献   
927.
Over the last 15 years, despite the lack of a specific strategy or a dedicated financial instrument to deal with invasive alien species (IAS), the European Commission (EC) has contributed to financing almost 300 projects addressing this issue, for a total budget exceeding 132 million EUR. Such figures are based on projects funded under two specific EU financial tools: LIFE and the RTD Framework Programmes. The contribution of the two programmes has been characterised by an overall positive trend over the years, in terms of both the number of projects and the budget spent. Such trend can be assumed to reflect an overall increase in both the awareness of the problem among wildlife managers and scientific institutions, and the willingness to pay by the EC institutions and the EU citizens in general. Such data might contribute to the development of a response indicator measuring ‘Trends in invasive alien species in Europe’, useful to assess progress toward the target of halting the loss of biodiversity by 2010—as a part of the SEBI 2010 process. The results may also contribute to assess the economic impact of IAS in Europe—in terms of costs for reduction and/or prevention of damages—and to support policy decisions and communication campaigns. Finally, the results are encouraging and support the need for the development and the implementation of a sound EU strategy on IAS, so as to regulate and optimise the administration of the available financial resources—whenever appropriate—on the basis of specific priorities.  相似文献   
928.
A novel metabolic pathway was found in the yeast Trichosporon moniliiforme WU-0401 for salicylate degradation via phenol as the key intermediate. When 20 mM salicylate was used as the sole carbon source for the growth of strain WU-0401, phenol was detected as a distinct metabolite in the culture broth. Analysis of the products derived from salicylate or phenol through reactions with resting cells and a cell-free extract of strain WU-0401 indicated that salicylate is initially decarboxylated to phenol and then oxidized to catechol, followed by aromatic ring cleavage to form cis-cis muconate.  相似文献   
929.
Non-indigenous arthropods are increasingly being introduced into new areas worldwide and occasionally they cause considerable ecological and economic harm. Many invasive arthropods particularly pose problems to areas of human habitation and native ecosystems. In these cases, the use of environmentally benign materials, such as host-specific entomopathogens, can be more desirable than broader spectrum control tactics that tend to cause greater non-target effects. The majority of successful eradication programs using arthropod pathogens have targeted invasive Lepidoptera with Bacillus thuringiensis kurstaki (Btk), such as eradication efforts against the gypsy moth, Lymantria dispar (L.), in North America and New Zealand. Both Btk and Lymantria dispar nucleopolyhedrovirus have been successfully used in efforts to limit the spread of L. dispar in the United States. For invasive arthropod species that are well established, suppression programs have successfully used arthropod-pathogenic viruses, bacteria, fungi and nematodes for either short- or long-term management. We will summarize the use of pathogens and nematodes in invasive arthropod management programs within a general context, and compare the use of microbes in gypsy moth management with diverse microbes being developed for use against other invasive arthropods.  相似文献   
930.
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