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41.
Junya Ono Jean W. H. Yong Koji Takayama Mohd Nazre Bin Saleh Alison K. S. Wee Takeshi Asakawa Orlex Baylen Yllano Severino G. SalmoIII Monica Suleiman Nguyen Xuan Tung Khin Khin Soe Sankararamasubramanian Halasya Meenakshisundaram Yasuyuki Watano Edward L. Webb Tadashi Kajita 《Conservation Genetics》2016,17(5):1137-1144
Bruguiera hainesii (Rhizophoraceae) is one of the two Critically Endangered mangrove species listed in the IUCN Red List of Threatened Species. Although the species is vulnerable to extinction, its genetic diversity and the evolutionary relationships with other Bruguiera species are not well understood. Also, intermediate morphological characters imply that the species might be of hybrid origin. To clarify the genetic relationship between B. hainesii and other Bruguiera species, we conducted molecular analyses including all six Bruguiera species using DNA sequences of two nuclear genes (CesA and UNK) and three chloroplast regions (intergenic spacer regions of trnL-trnF, trnS-trnG and atpB-rbcL). For nuclear DNA markers, all nine B. hainesii samples from five populations were heterozygous at both loci, with one allele was shared with B. cylindrica, and the other with B. gymnorhiza. For chloroplast DNA markers, the two haplotypes found in B. hainesii were shared only by B. cylindrica. These results suggested that B. hainesii is a hybrid between B. cylindrica as the maternal parent and B. gymnorhiza as the paternal one. Furthermore, chloroplast DNA haplotypes found in B. hainesii suggest that hybridization has occurred independently in regions where the distribution ranges of the parental species meet. As the IUCN Red List of Threatened Species currently excludes hybrids (except for apomictic plant hybrids), the conservation status of B. hainesii should be reconsidered. 相似文献
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43.
Takayama T Morelli AE Onai N Hirao M Matsushima K Tahara H Thomson AW 《Journal of immunology (Baltimore, Md. : 1950)》2001,166(12):7136-7143
44.
Takayama S Chung SJ Igarashi Y Ichikawa Y Sepp A Lechler RI Wu J Hayashi T Siuzdak G Wong CH 《Bioorganic & medicinal chemistry》1999,7(2):401-409
A combined rational and library approach was used to identify bisphosphonates (IC50 = 20 microM) and galactose type 1-N-iminosugar (IC50=45 microM) as novel motifs for selective inhibition of beta-1,4-galactosyltransferase (beta-1,4-GalT) and alpha-1,3-galactosyltransferase (alpha-1,3-GalT), respectively. Our results demonstrate that, though these two galactosyltransferases both utilize the same donor sugar-nucleotide (UDP-Gal), the difference in their mechanisms can be utilized to design donor sugar or nucleotide analogues with inhibitory activities selective for only one of the galactosyltransferases. Investigation of beta-1,4-GalT inhibition using UDP-2-deoxy-2-fluorogalactose (UDP-2-F-Gal), UDP, and bisphosphonates, also led to the observation of metal dependent inhibition of beta-1,4-GalT. These observations and the novel inhibitor motifs identified in this study pave the way for the design and identification of even more potent and selective galactosyltransferase inhibitors. 相似文献
45.
In vivo priming of natural killer T cells by dendritic cells pulsed with hepatoma-derived acid-eluted substances 总被引:2,自引:0,他引:2
Ishii R Shimizu M Nakagawa Y Shimizu K Tanaka S Takahashi H 《Cancer immunology, immunotherapy : CII》2004,53(5):383-390
Many murine tumor cells express not only individual haplotype-matched class I MHC molecules, but also species-specific CD1d molecules. The former class I MHC molecules generally present internally synthesized tumor-derived peptide antigens to highly specific CD8+ cytotoxic T lymphocytes (CTLs) in acquired immunity. In contrast, the latter CD1d molecules may present tumor-associated glycolipid antigens to broadly crossreactive natural killer T (NKT) cells, which might correlate with controlling tumor metastasis. Here, we showed that murine hepatoma cell line Hepa1-6-derived acid-eluted substances might contain both Db class I MHC-restricted antigens and CD1d-restriced substances, which could sensitize not only syngeneic bone marrow-derived DCs (BM-DCs), but also allogeneic BM-DCs expressing haplotype-mismatched class I MHC and species-specific CD1d molecules. To our surprise, intravenous (i.v.) immunization of C57BL/6 mice with the former syngeneic BM-DCs carrying acid-eluted materials primed both CD4–CD8– and CD8+ NKT cells in the spleen, whereas immunization with the latter allogeneic BM-DCs loaded the tumor-derived substances primed CD4–CD8–, but not CD8+ NKT cells. The findings shown in the present study will open a new area for cancer immunotherapy using allogeneic DCs and tumor-derived acid-eluted substances.Abbreviations CTLs
cytotoxic T lymphocytes
- NKT
natural killer T
- BM-DCs
bone marrow-derived dendritic cells
- CTM
complete T-cell medium
- FCS
fetal calf serum
- MMC
mitomycin C
- TCRs
T cell receptors 相似文献
46.
Qing G Ma LC Khorchid A Swapna GV Mal TK Takayama MM Xia B Phadtare S Ke H Acton T Montelione GT Ikura M Inouye M 《Nature biotechnology》2004,22(7):877-882
Overexpression of proteins in Escherichia coli at low temperature improves their solubility and stability. Here, we apply the unique features of the cspA gene to develop a series of expression vectors, termed pCold vectors, that drive the high expression of cloned genes upon induction by cold-shock. Several proteins were produced with very high yields, including E. coli EnvZ ATP-binding domain (EnvZ-B) and Xenopus laevis calmodulin (CaM). The pCold vector system can also be used to selectively enrich target proteins with isotopes to study their properties in cell lysates using NMR spectroscopy. We have cloned 38 genes from a range of prokaryotic and eukaryotic organisms into both pCold and pET14 (ref. 3) systems, and found that pCold vectors are highly complementary to the widely used pET vectors. 相似文献
47.
48.
Xue Y Hieda Y Kimura K Takayama K Fujihara J Tsujino Y 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,811(1):53-58
Kinetic characteristics and toxic effects of benzalkonium chloride (BZK) following injection via jugular vein (JV), femoral artery (FA) and oral administration (PO) were experimentally investigated using rats. The BZK concentrations in blood and tissues (lung, liver and kidney) were determined by high-performance liquid chromatography with solid phase extraction. Toxic doses of 15 and 250 mg/kg of BZK were used for intravascular (JV and FA) and PO administration, respectively. The fatal effects appeared soon after the dose in JV-rats, while delayed in FA- or PO-rats. The blood BZK concentrations and the elimination half-lives were similar between JV- and FA-rats, while the distribution of BZK in tissues was slightly different. In PO administration, the rats that aspirated BZK into their lungs had some symptoms, while the rats that did not aspirate BZK appeared to be normal. The BZK concentrations in blood and tissues were significantly higher in the aspirated PO-rats. The toxic degree of BZK was correlated with the BZK concentration in orally dosed rats. Lung and kidney had higher BZK concentrations compared to blood or liver, and they could be the target organs of BZK.Keyword: Benzalkonium chloride 相似文献
49.
Kai M Kaito C Fukamachi H Higo T Takayama E Hara H Ohya Y Igarashi K Shiokawa K 《Cell research》2003,13(3):147-158
In Xenopus, injection of S-adenosylmethionine decarboxylase (SAMDC) mRNA into fertilized eggs or 2-cell stage embryos induces massive cell dissociation and embryo-lysis at the early gastrula stage due toactivation of the maternal program of apoptosis. We injected SAMDC mRNA into only one of the animalside blastomeres of embryos at different stages of cleavage, and examined the timing of the onset of theapoptotic reaction. In the injection at 4-and 8-cell stages, a considerable number of embryos developed intotadpoles and in the injection at 16-and 32-cell stages, all the embryos became tadpoles, although tadpolesobtained were sometimes abnormal. However, using GFP as a lineage tracer, we found that descendant cellsof the blastomere injected with SAMDC mRNA at 8-to 32-cell stages are confined within the blastocoel atthe early gastrula stage and undergo apoptotic cell death within the blastocoel, in spite of the continued development of the injected embryos. These results indicate that cells overexpressed with SAMDC undergo apoptotic cell death consistently at the early gastrula stage, irrespective of the timing of the mRNA injection.We assume that apoptosis is executed in Xenopus early gastrulae as a “fall-safe“ mechanism to eliminate physiologically-severely damaged cells to save the rest of the embryo. 相似文献
50.
Oka S Tsuchie A Tokumura A Muramatsu M Suhara Y Takayama H Waku K Sugiura T 《Journal of neurochemistry》2003,85(6):1374-1381
2-Eicosa-5',8',11',14'-tetraenylglycerol (2-AG ether, HU310, noladin ether) is a metabolically stable ether-linked analogue of 2-arachidonoylglycerol (2-AG), an endogenous cannabinoid receptor ligand. 2-AG ether has been used as a valuable experimental tool by a number of investigators. Recently, several groups reported that 2-AG ether is present in mammalian brains. We examined in detail whether 2-AG ether actually exists in the brains of various mammalian species. We found that 2-AG ether is not present, at least in an appreciable amount, in the rat brain by gas chromatography-mass spectrometry analysis and fluorometric high performance liquid chromatography analysis. The level of 2-AG ether in the rat brain was below 0.2 pmol/g brain, if at all present. Similar results were obtained for the mouse brain, hamster brain, guinea-pig brain and pig brain. The fact that 2-AG ether was not detected in the brains of various mammalian species is consistent with the fact that an ether bond is formed through enzymatic replacement of the fatty acyl moiety of 1-acyl dihydroxyacetone phosphate by a fatty alcohol, the resultant 1-O-alkyl dihydroxyacetone phosphate being a common intermediate of the biosynthesis of ether-linked lipids in mammalian tissues. It is rather questionable whether 2-AG ether is present in appreciable amounts in the brain and acts as an 'endogenous' cannabinoid receptor ligand. 相似文献