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91.
c-Jun NH2-terminal kinases (JNKs) and phosphatidylinositol 3-kinase (PI3-K) play critical roles in chronic diseases such as cancer, type II diabetes, and obesity. We describe here the binding of quercetagetin (3,3′,4′,5,6,7-hydroxyflavone), related flavonoids, and SP600125 to JNK1 and PI3-K by ATP-competitive and immobilized metal ion affinity-based fluorescence polarization assays and measure the effect of quercetagetin on JNK1 and PI3-K activities. Quercetagetin attenuated the phosphorylation of c-Jun and AKT, suppressed AP-1 and NF-κB promoter activities, and also reduced cell transformation. It attenuated tumor incidence and reduced tumor volumes in a two-stage skin carcinogenesis mouse model.Our crystallographic structure determination data show that quercetagetin binds to the ATP-binding site of JNK1. Notably, the interaction between Lys55, Asp169, and Glu73 of JNK1 and the catechol moiety of quercetagetin reorients the N-terminal lobe of JNK1, thereby improving compatibility of the ligand with its binding site. The results of a theoretical docking study suggest a binding mode of PI3-K with the hydroxyl groups of the catechol moiety forming hydrogen bonds with the side chains of Asp964 and Asp841 in the p110γ catalytic subunit. These interactions could contribute to the high inhibitory activity of quercetagetin against PI3-K. Our study suggests the potential use of quercetagetin in the prevention or therapy of cancer and other chronic diseases.  相似文献   
92.
Symplocarpus L. (Araceae) is a disjunct genus including S. foetidus (L.) Nutt. var. latissimus (Makino) S. Hara, S. nipponicus Makino, and S. nabekuraensis Otsuka & K. Inoue in temperate eastern Asia; S. egorovii N. S. Pavlova & V. A. Nechaev in the Russian far east; and S. foetidus (L.) Nutt. in temperate northeastern North America. For the first time, pollen morphology of Symplocarpus was investigated by light and scanning electron microscopes. Symplocarpus foetidus var. latissimus and S. foetidus had reticulate surfaces and rounded (obtuse), long, equatorial axis tips, whereas S. nipponicus had microreticulate surfaces and acute tips. Symplocarpus foetidus in North America had larger pollen grains than S. foetidus var. latissimus in eastern Asia. Thus, based on pollen characteristics, S. foetidus var. latissimus is more closely related to S. foetidus than to S. nipponicus. Other lines of evidence, such as molecular phylogenetic studies and phenology, support the phylogenetic relationships among these species proposed in this study. The slightly modified acetolysis procedure conducted in this paper is a promising application to study weak exine or exineless pollen grains.  相似文献   
93.
PRA1 has been reported as a prenylated Rab acceptor containing GDF activity in human, rat and yeast. Its existence was also proved in plants by sequence analysis, anticipating its important role as a Rab effector, but defined roles of the plant PRA1 homologs remain to be obscure. Here, to get an insight for their role, we performed yeast two-hybrid screen using the OsRab7 as bait and first isolated the OsPRA1, a putative prenylated Rab acceptor, interacting with this protein. Detailed interaction analysis showed that OsPRA1 interacted not only with GDP-bound OsRab7, but also with several other Rab GTPases involved in vacuolar trafficking, in a prenylation-dependent manner. In addition, GFP-fusion analysis demonstrated that OsPRA1 localized to the prevacuolar compartment, and RNA gel blot analysis revealed its significant expression in rice green-aerial tissues such as shoots and mature stems. These results suggest that OsPRA1 may function as a Rab effector for vacuolar trafficking in the plant system.  相似文献   
94.
Herbal medicine has been used in the orient for thousands of years to treat large and small ailments, including microbial infections. Although there are treatments for influenza virus infection, there is no treatment for drug-resistant viruses. It is time that we explored and exploited the multi-component nature of herbal extracts as multi-drug combination therapies. Here, we present data on the anti-influenza virus effect of a medicinal mushroom, Phellinus igniarius. The P. igniarius water extract was effective against influenza A and B viruses, including 2009 pandemic H1N1, human H3N2, avian H9N2, and oseltamivir-resistant H1N1 viruses. Virological assays revealed that the extract may interfere with one or more early events in the influenza virus replication cycle, including viral attachment to the target cell. Therefore, our results provide new insights into the use of P. igniarius as an anti-influenza medicine.  相似文献   
95.
Microalgae are major primary producers of organic matter in aquatic environments through their photosynthetic activities. Fermented microalga (Pavlova lutheri Butcher) preparation (FMP) is the product of yeast fermentation by Hansenula polymorpha. It was tested for the antioxidant activities including lipid peroxidation inhibitory activity, free‐radical‐scavenging activity, inhibition of reactive oxygen species (ROS) on mouse macrophages (RAW264.7 cell), and inhibited myeloperoxidase (MPO) activity in human myeloid cells (HL60). FMP exhibited the highest antioxidant activity on free‐radical scavenging, inhibitory intracellular ROS, and inhibited MPO activity. MTT [3‐(4,5‐dimethyl‐2‐yl)‐2,5‐diphenyltetrazolium bromide] assay showed no cytotoxicity in mouse macrophages (RAW264.7 cell), human myeloid cells (HL60), and human fetal lung fibroblast cell line (MRC‐5). Furthermore, the antioxidative mechanism of FMP was evaluated by protein expression levels of antioxidant enzyme (superoxide dismutase [SOD] and glutathione [GSH]) using Western blot. The results obtained in the present study indicated that FMP is a potential source of natural antioxidant.  相似文献   
96.
Adult stem cells have a great potential to treat various diseases. For these cell-based therapies, adipose-derived stem cells (ADSCs) are one of the most promising stem cell types, including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). ESCs and iPSCs have taken center stage due to their pluripotency. However, ESCs and iPSCs have limitations in ethical issues and in identification of characteristics, respectively. Unlike ESCs and iPSCs, ADSCs do not have such limitations and are not only easily obtained but also uniquely expandable. ADSCs can differentiate into adipocytes, osteoblasts, chondrocytes, myocytes and neurons under specific differentiation conditions, and these kinds of differentiation potential of ADSCs could be applied in regenerative medicine e.g., skin reconstruction, bone and cartilage formation, etc. In this review, the current status of ADSC isolation, differentiation and their therapeutic applications are discussed.  相似文献   
97.
This study presents a simple and fast method for the identification of bifidobacteria using a thin layer chromatographic (TLC) analysis of the short chain fatty acids in a culture broth. When the chromatogram was sprayed with the indicator solution (methyl red-bromophenol blue in 70% ethanol), lactic acid exhibited two red spots, and acetic acid, propionic acid, and butyric acid all produced blue spots. Succinic acid and citric acid produced yellow and dark yellow spot, respectively. In addition, these organic acids showed different R(f) values. The total time taken to analyze the organic acids in the 10 bacterial culture broths using the proposed method was approximately 50 min. The proposed TLC method was used to analyze the organic acids in culture broths of the following strains, five Bifidobacterium species. (Bifidobacterium longum, B. breve, B. infantis, B. bifidum, and B. adolescentis) and five other lactic acid bacteria strains (Lactobacillus casei, L. bulgaricus, L. acidophilus, Streptococcus thermophilus, and S. lactis). Both spots of lactic acid and acetic acid were detected on all the TLC plates from the five bifidobacterial culture broths. The five other lactic acid bacterial culture broths, however, only exhibited lactic acid spots. Accordingly, the proposed TLC method would appear to be a useful tool for rapid identification of Bifidobacterium spp. at the genus level.  相似文献   
98.
99.
To search for candidate control agents against Aeromonas salmonicida subsp. salmonicida infections in aquaculture, one bacteriophage (phage), designated as PAS-1, was isolated from the sediment samples of the rainbow trout (Oncorhynchus mykiss) culture farm in Korea. The PAS-1 was morphologically classified as Myoviridae and possessed approximately 48 kb of double-strand genomic DNA. The phage showed broad host ranges to other subspecies of A. salmonicida as well as A. salmonicida subsp. salmonicida including antibiotic-resistant strains. Its latent period and burst size were estimated to be approximately 40 min and 116.7 PFU/cell, respectively. Furthermore, genomic and structural proteomic analysis of PAS-1 revealed that the phage was closely related to other Myoviridae phages infecting enterobacteria or Aeromonas species. The bacteriolytic activity of phage PAS-1 was evaluated using three subspecies of A. salmonicida strain at different doses of multiplicity of infection, and the results proved to be efficient for the reduction of bacterial growth. Based on these results, PAS-1 could be considered as a novel Aeromonas phage and might have potentiality to reduce the impacts of A. salmonicida infections in aquaculture.  相似文献   
100.
Sera from rabbits were infected with Vibrio vulnificus containing an antibody against major outer membrane protein (MOMP). MOMP of V. vulnificus ATCC 27562 were isolated and purified by Sarkosyl and TritonX-100 dual treatment. Molecular size of MOMP was identified as 36-kDa on 13% SDS-PAGE. The sequence of the first 26 amino acid residues from the N-terminal end of the protein is AELYNQDGTSLDMGGRAEARLSMKDG , which is a perfect match with OmpU of V. vulnificus CMCP6 and YJ016. MOMP specific IgM and IgG were investigated in groups of mice. The group of mice immunized with MOMP and Alum showed higher levels of IgG2b than the group immunized with only MOMP. Vaccination with MOMP resulted in protective antibodies in the mouse infection experiment.  相似文献   
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