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151.
A study was done to determine how lipid microspheres (LM) containing prostaglandin E1 (lipo PGE1) accumulate in injured arterial tissue. After administration of lipo PGE1 labeled with a fluorescence probe, 1,1'-dioctadecyl-3, 3, 3',3'-tetramethyl-indocarbocyanine perchlorate (DiI-lipo PGE1) to rats 14 of days after balloon injury of the carotid artery, localization into the injured site was examined using a fluorescence confocal laser scanning microscope (CLSM). In contrast with the normal carotid artery, DiI-lipo PGE1 accumulated remarkably in neointima of the injured site which was occupied mainly by the migration of the proliferating and quiescent vascular smooth muscle cells (SMC). In vitro cellular uptake of DiI-lipo PGE1 was semi-quantitatively measured using CLSM, regarding differentiated and proliferative phenotypes of human vascular SMC, compared with the human endothelial cells (EC) and mouse fibroblasts. The differentiated SMC incorporated DiI-lipo PGE1 to equal or a higher level of the proliferative phenotype, and was significantly higher than EC and fibroblasts. The uptake of DiI-lipo PGE1 by both SMC and EC was inhibited at 4 degrees C, by dansylcadaverine and excessive LM, but was unaffected by cytochalasin B. These results suggest that the uptake of DiI-lipo PGE1 by SMC plays an important role in localization of DiI-lipo PGE1 at the injured site, and that the uptake seems to be a receptor mediated endocytosis. 相似文献
152.
Haginaka J Kagawa C 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,804(1):19-24
Uniformly sized molecularly imprinted polymers (MIPs) for d-chlorpheniramine (CP) and -brompheniramine (BP) have been prepared by a multi-step swelling and polymerization method using methacrylic acid (MAA) or 2-(trifluoromethyl)acrylic acid (TFMAA) and ethylene glycol dimethacrylate (EDMA) as a functional monomer and cross-linker, respectively. The retentive and enantioselective properties of CP, BP and their structurally related compounds on the MIPs were evaluated using hydro-organic mobile phases. CP and BP enantiomers were retained the most as a monovalent cation on MAA-co-EDMA polymers and a divalent cation on TFMAA-co-EDMA polymers. Ion exchange and hydrophobic interactions could mainly work for the retention and enantioseparation of CP and BP on both MAA-co-EDMA and TFMAA-co-EDMA polymers in hydro-organic mobile phases. Though the respective MIPs gave the highest enantioselectivity for the template molecule, cross-reactivity for CP and BP was observed with them. 相似文献
153.
Natural hybridization in Taraxacum between native sexual diploids and introduced agamospermous triploids occurring in Japan was studied by means of chloroplast
DNA (cpDNA) marker. We first determined the nucleotide sequences between trnT (UGU) and trnF (GAA) of cpDNA for 22 plants obtained from Japan and Europe. The sequences analyzed were about 1,574 base pairs long. Among
all accessions, the total numbers of polymorphic characters were 56 nucleotide substitutions, three insertions/deletions (ins/dels),
and one repeat number polymorphism of mononucleotide motif. Of these polymorphic characters, four nucleotides and one ins/del
were applicable in the discrimination between Japanese and European taxa of dandelions. We selected the ins/del in an intergenic
region between trnL (UAA) 3′ exon and trnF (GAA) as a cpDNA marker. Using a newly developed cpDNA marker, 225 plants of putative Taraxacum officinale collected from 11 populations in Niigata City were investigated. Eighty-two percent of them showed a Japanese haplotype of
cpDNA, and they were regarded as hybrids. Compared with the previous studies, it is likely that the prevalence of the hybrid
plants is a general phenomena at least in urban areas in Japan. The validity of the cpDNA marker for screening Taraxacum hybrids is discussed.
Electronic Publication 相似文献
154.
Tsuji K Mizumoto K Sudo H Kouyama K Ogata E Matsuoka M 《Biochemical and biophysical research communications》2002,295(3):621-629
p19(ARF) is a potent tumor suppressor. By inactivating Mdm2, p19(ARF) upregulates p53 activities to induce cell cycle arrest and sensitize cells to apoptosis in the presence of collateral signals. It has also been demonstrated that cell cycle arrest is induced by overexpressed p19(ARF) in p53-deficient mouse embryonic fibroblasts, only in the absence of the Mdm2 gene. Here, we show that apoptosis can be induced without additional apoptosis signals by expression of p19(ARF) using an adenovirus-mediated expression system in p53-intact cell lines as well as p53-deficient cell lines. Also, in primary mouse embryonic fibroblasts (MEFs) lacking p53/ARF, p53-independent apoptosis is induced irrespective of Mdm2 status by expression of p19(ARF). In agreement, p19(ARF)-mediated apoptosis in U2OS cells, but not in Saos2 cells, was attenuated by coexpression of Mdm2. We thus conclude that there is a p53-independent pathway for p19(ARF)-induced apoptosis that is insensitive to inhibition by Mdm2. 相似文献
155.
Pretreatment procedure for the microdetermination of chondroitin sulfate in plasma and urine 总被引:1,自引:0,他引:1
Sakai S Onose J Nakamura H Toyoda H Toida T Imanari T Linhardt RJ 《Analytical biochemistry》2002,302(2):169-174
A new, simple, and rapid pretreatment method for the determination of chondroitin sulfate, dermatan sulfate, and hyaluronan from urine and blood plasma samples has been developed. Plasma proteins were first converted into small peptides by digestion using a nonspecific protease, actinase E, and the resulting small peptides were removed by centrifugal filtration. The retained, residual crude glycosaminoglycans, including chondroitin/dermatan sulfates and hyaluronan, were converted into unsaturated disaccharides through the action of chondroitin sulfate lyses. Next, these disaccharides were recovered and purified using centrifugal filtration together with DeltaDi-UA2S, added as an internal standard. The filtered disaccharide mixture was analyzed by HPLC with fluorometric postcolumn derivatization using 2-cyanoacetamide as a fluorogenic reagent. This method was applied to a pharmacokinetic study of chondroitin sulfate administered intravenously to mice. The half-life of the administered chondroitin sulfates, having molecular masses from 6 to 50 kDa, varied depending on their molecular sizes. This new method should be useful for studies on the metabolic fate of exogenously administered glycosaminoglycans in small experimental animals. 相似文献
156.
Hiromura M Chino H Sonoda T Sakurai H 《Biochemical and biophysical research communications》2000,275(2):394-400
Copper chaperone is an essential cytosolic factor that maintains copper homeostasis in living cells. Cytosolic metallochaperones have been recently identified in plant, yeast, rodents, and human cells. During our investigation, we found a new member of the copper chaperone family for copper/zinc superoxide dismutase, which was cloned from rats. The new copper chaperone was named rCCS (rat Copper Chaperone for Superoxide dismutase). The cDNA of rCCS was found to have a length of 1094 bp, and the protein analyzed from the cDNA was deduced to contain 274 amino acids. The amino acid sequence of rCCS consists of three domains: A metal binding domain, which has a MXCXXC motif in domain I, a homolog of the Cu/Zn SOD in domain II, and a CXC motif in domain III. The binding of rCCS to Cu/Zn SOD was analyzed by GST column binding assay, and the domain II of rCCS was found to be essential for binding to Cu/Zn SOD, which in turn activates Cu/Zn SOD. 相似文献
157.
158.
Elizabeth Watson Samira Fargali Haruka Okamoto Masato Sadahiro Ronald E Gordon Tandra Chakraborty Mark W Sleeman Stephen R Salton 《BMC physiology》2009,9(1):19-20
Background
Previous studies of mixed background mice have demonstrated that targeted deletion of Vgf produces a lean, hypermetabolic mouse that is resistant to diet-, lesion-, and genetically-induced obesity. To investigate potential mechanism(s) and site(s) of action of VGF, a neuronal and endocrine secreted protein and neuropeptide precursor, we further analyzed the metabolic phenotypes of two independent VGF knockout lines on C57Bl6 backgrounds. 相似文献159.
Haruka Minami Katsuhisa Tashiro Atsumasa Okada Nobue Hirata Tomoko Yamaguchi Kazuo Takayama Hiroyuki Mizuguchi Kenji Kawabata 《PloS one》2015,10(6)
The blood brain barrier (BBB) is formed by brain microvascular endothelial cells (BMECs) and tightly regulates the transport of molecules from blood to neural tissues. In vitro BBB models from human pluripotent stem cell (PSCs)-derived BMECs would be useful not only for the research on the BBB development and function but also for drug-screening for neurological diseases. However, little is known about the differentiation of human PSCs to BMECs. In the present study, human induced PSCs (iPSCs) were differentiated into endothelial cells (ECs), and further maturated to BMECs. Interestingly, C6 rat glioma cell-conditioned medium (C6CM), in addition to C6 co-culture, induced the differentiation of human iPSC-derived ECs (iPS-ECs) to BMEC-like cells, increase in the trans-endothelial electrical resistance, decreased in the dextran transport and up-regulation of gene expression of tight junction molecules in human iPS-ECs. Moreover, Wnt inhibitors attenuated the effects of C6CM. In summary, we have established a simple protocol of the generation of BMEC-like cells from human iPSCs, and have demonstrated that differentiation of iPS-ECs to BMEC-like cells is induced by C6CM-derived signals, including canonical Wnt signals. 相似文献
160.
Nobuaki Niwa Miguel Vazquez Archdale Takashi Matsuoka Aina Kawamoto Haruka Nishiyama 《Central European Journal of Biology》2014,9(1):80-85
A study was performed on the microhabitat distribution and some aspects of behaviour of the ectosymbiotic branchiobdellidan Holtodrilus truncatus (Annelida, Clitellata) found on the freshwater shrimp that inhabit the Sugo River, Hyogo Prefecture, western Japan. Observations on shrimp that were collected from the Sugo River (2003 to 2011) confirmed that the host shrimp is Neocaridina spp. (Atyidae). The attachment location on the host shrimp was predominately between the 1st pleopod and the 5th pereopod (55.3%). The reproductive method of H. truncatus is hemaphroditism. The cocoon was found only inside the carapace of the host shrimp. The cocoon was transparent and contained a maximum of 14 juvenile worms (developing embryos). When hatching approached, H. truncatus’s worms became elongated and slender, and only one worm hatched out at a time. When Holtodrilus truncatus was removed from its host and was maintained in river water without any food, it survived for a maximum of 46 days. In a host exchange experiment, where we provided several other freshwater shrimp species, Palaemonidae fed on H. truncatus. Moreover, Palaemon paucidens and Macrobrachium nipponense from Lake Biwa also preyed upon H. truncatus. The possible symbiotic relationship between H. truncatus and Neocaridina spp. (family Atyidae) is further discussed. 相似文献