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21.
Sato Y Igarashi Y Hakamata Y Murakami T Kaneko T Takahashi M Seo N Kobayashi E 《Biochemical and biophysical research communications》2003,311(2):478-481
Because serum albumin is specifically produced by mature hepatocytes, detection system of albumin producing cells could be a valuable tool to visualize liver regeneration or development. We have developed here an albumin enhancer/promoter-driven Alb-DsRed2 Tg rat that expresses DsRed2, having liver-specific reporter gene expression of red fluorescent protein. To study the transdifferentiation of bone marrow cells (BMCs) into albumin producing cells, BMCs from the Alb-DsRed2 Tg rat were injected into rats having acute liver damage caused by 2-acetylaminofluorene plus carbon tetrachloride and chronic liver damage by repeated administration of CCl(4). DsRed2-positive cells were generated in the recipient liver after BMC injection. The number of transdifferentiated DsRed2-positive cells in chronic liver injury model was increased comparing with that in acute injury model. We propose that the Alb-DsRed2 Tg rat is well suited to studying in vivo liver regeneration. 相似文献
22.
Seo?Ho?Lee Hyun?Soo?Lee Shin?Young?Lee Sung?Jin?Hwang Baek?Hwang Jae?Heun?Kim Hyeon?Yong?LeeEmail author 《Journal of Plant Biology》2002,45(1):44-48
We tested the influence of extracts from three medicinal herbs —Salvia miltiorrhiza, Schizandra chinensis, andEugenia caryophyllata — on activity of the nematodeRhabditis elongate. Treatment with f.caryophyllata was most useful, causing the greatest decrease in populations and mobility, but did not have any detrimental effect on the
initial growth of the host microorganism,Escherichia coli. For example, when 0.5 g/L of the extract was added to an inoculated liquid culture, we counted 710 nematodes/mL, with a multiplication
rate 5 times greater than the initial population. This was in contrast to the control sample, which had a count of 1100 nematodes/mL
and a growth ratio of 11. For our field test, nematode mobility in the presence of the extract also decreased, to 6.8 mm/day,
compared with 20 mm/day for the control. Likewise, when 1.0 g/L of the extract was added to the soil, the total number of
nematodes was reduced to only 30- to 40% of the control population. 相似文献
23.
Nakamoto T Suzuki T Huang J Matsumura T Seo S Honda H Sakai R Hirai H 《Biochemical and biophysical research communications》2002,294(3):635-641
p130(Cas) (Cas) is a docking protein that becomes tyrosine phosphorylated in v-Src- or v-Crk-transformed cells and in integrin-stimulated cells. Cas -/- fibroblasts show defects in stress fiber formation, cell spreading, cell migration, and transformation by activated Src. To further characterize the role of Cas in signaling, we compared the expression profile in Cas -/- fibroblasts with that in Cas-re-expressing fibroblasts using the microarray methods. In Cas -/- fibroblasts, the expression of heme oxygenase 1 and caveolin-1 was reduced, but the expression of procollagen 1 alpha 1, procollagen 3 alpha 1, procollagen 11 alpha 1, elastin, periostin, TSC-36, and MARCKS was enhanced. The domains in Cas necessary for the change varied among these genes. Activated Src reduced the expression of most of these genes both in Cas -/- and in Cas +/+ fibroblasts. These results suggest the existence of signaling pathways that emanate from Cas to gene expression. 相似文献
24.
25.
Lee HS Kang IM Lee HW Seo JH Ryu JH Choi SJ Lee MJ Jeong SY Cho YW Lee KT 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,863(1):158-162
A simple and specific method using a one-step liquid-liquid extraction (LLE) with butyl acetate followed by high performance liquid chromatography (HPLC) coupled with positive ion electrospray ionization tandem mass spectrometry (ESI-MS/MS) detection was developed for the determination of etodolac in human plasma, using indomethacin as an internal standard (IS). Chromatographic separation was performed isocratically using a Capcellpak MGII C(18) column with 65% acetonitrile and 35% water containing 10mM ammonium formate (adjusted to pH 3.5 with formic acid). Acquisition was performed in multiple reaction monitoring (MRM) mode by monitoring the transitions: m/z 287.99>172.23 for etodolac and m/z 357.92>139.01 for IS. The method was validated to determine its selectivity, linearity, sensitivity, precision, accuracy, recovery and stability. The limit of quantitation (LLOQ) was 0.1microg/mL with a relative standard deviation of less than 15%. The devised method provides an accurate, precise and sensitive tool for determining etodolac levels in plasma. 相似文献
26.
Joon Ha Park Choong Hyun Lee In Hye Kim Ji Hyeon Ahn Jeong-Hwi Cho Bing Chun Yan Jae-Chul Lee Tae Hun Lee Jeong Yeol Seo Jun Hwi Cho Moo-Ho Won Il-Jun Kang 《Neurochemical research》2013,38(12):2640-2649
Glucose is a main energy source for normal brain functions. Glucokinase (GK) plays an important role in glucose metabolism as a glucose sensor, and GK activity is modulated by glucokinase regulatory protein (GKRP). In this study, we examined the changes of GK and GKRP immunoreactivities in the gerbil hippocampus after 5 min of transient global cerebral ischemia. In the sham-operated-group, GK and GKRP immunoreactivities were easily detected in the pyramidal neurons of the stratum pyramidale of the hippocampus. GK and GKRP immunoreactivities in the pyramidal neurons were distinctively decreased in the hippocampal CA1 region (CA), not CA2/3, 3 days after ischemia–reperfusion (I–R). Five days after I–R, GK and GKRP immunoreactivities were hardly detected in the CA1, not CA2/3, pyramidal neurons; however, at this point in time, GK and GKRP immunoreactivities were newly expressed in astrocytes, not microglia, in the ischemic CA1. In brief, GK and GKRP immunoreactivities are changed in pyramidal neurons and newly expressed in astrocytes in the ischemic CA1 after transient cerebral ischemia. These indicate that changes of GK and GKRP expression may be related to the ischemia-induced neuronal damage/death. 相似文献
27.
Ho Seong Seo George Minasov Ravin Seepersaud Kelly S. Doran Ievgeniia Dubrovska Ludmilla Shuvalova Wayne F. Anderson Tina M. Iverson Paul M. Sullam 《The Journal of biological chemistry》2013,288(50):35982-35996
The serine-rich repeat glycoproteins of Gram-positive bacteria comprise a large family of cell wall proteins. Streptococcus agalactiae (group B streptococcus, GBS) expresses either Srr1 or Srr2 on its surface, depending on the strain. Srr1 has recently been shown to bind fibrinogen, and this interaction contributes to the pathogenesis of GBS meningitis. Although strains expressing Srr2 appear to be hypervirulent, no ligand for this adhesin has been described. We now demonstrate that Srr2 also binds human fibrinogen and that this interaction promotes GBS attachment to endothelial cells. Recombinant Srr1 and Srr2 bound fibrinogen in vitro, with affinities of KD = 2.1 × 10−5 and 3.7 × 10−6
m, respectively, as measured by surface plasmon resonance spectroscopy. The binding site for Srr1 and Srr2 was localized to tandem repeats 6–8 of the fibrinogen Aα chain. The structures of both the Srr1 and Srr2 binding regions were determined and, in combination with mutagenesis studies, suggest that both Srr1 and Srr2 interact with a segment of these repeats via a “dock, lock, and latch” mechanism. Moreover, properties of the latch region may account for the increased affinity between Srr2 and fibrinogen. Together, these studies identify how greater affinity of Srr2 for fibrinogen may contribute to the increased virulence associated with Srr2-expressing strains. 相似文献
28.
Ji-Yun Min Seung-Mi Kang Dong-Jin Park Yong-Duck Kim Ha-Na Jung Jae-Kyung Yang Won-Teak Seo Seon-Won Kim Chandrakant S. Karigar Myung-Suk Choi 《Biotechnology and Bioprocess Engineering》2006,11(4):372-376
Ferulic acid is a phenolic compound that serves as a major biosynthetic precursor of vanillin in higher plants. We investigated
the ability of the 3 commercial enzymes—Ultraflo L, Viscozyme L, and α-Amylase—to induce the release ferulic acid from theIpomoea batatas L. (sweet potato) stem. The rate of release for ferulic acid was optimal when Ultraflo L (1.0%) was used compared with the
other enzymes, whereas Viscozyme L was most effective for the release of vanillic acid and vanillin. Thus, these enzymes may
be useful for the large-scale production of ferulic acid and other phenolic compounds from sweet potato stem. 相似文献
29.
Do Geum-Sook Seo Bong-Bo Ko Jong-Min Lee Seon-Hee Pak Jae-Hong Kim In-Sun Song Seung-Dal 《Plant Cell, Tissue and Organ Culture》1999,57(2):113-119
The effects of basal media and growth regulators on callus initiation and shoot regeneration have been investigated in wild
Allium tuberosum (2n = 4x = 32). Callus initiation was greatest from flower bud explants cultured on MS medium supplemented
with 2,4-D and BA at 1 mg l−1 each. Maximum number of shoots was obtained from callus grown on MS medium supplemented with NAA and BA at 0.2 and 2 mg l−1, respectively. The chromosome analysis of regenerants derived from callus revealed variation in ploidy, such as 2n = 28,
29, 30, 31, 33 as well as normal tetraploid. During the culture period for two generations, one aneuploid regenerant with
2n = 30 (named At30) showed better viability and growth than tetraploid plants and other aneuploid variants. In a karyotypic
analysis of At30, the chromosomal positions of 5S and 18S-5.8S-26S rDNA were physically mapped by fluorescent in situ hybridization
and compared to chromosomes of wild type A. tuberosum. Both wild type A. tuberosum and At30 exhibited two sets of 5S rDNA
sites, one on the proximal position of the short arm of chromosome 3, and the other on the intercalary region on the long
arm of chromosome 6. There was one 18S-5.8S-26S rDNA site in the secondary constriction including flanking short chromosomal
segments of satellite and terminal regions on the short arm of chromosome 8 in wild type A. tuberosum. However, At30 showed
only three labelled chromosome 8 indicating that this was one of the lost chromosomes of At30.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
30.
Facilitation of Expression and Purification of an Antimicrobial Peptide by Fusion with Baculoviral Polyhedrin in Escherichia coli 总被引:2,自引:0,他引:2
Quande Wei Young Soo Kim Jeong Hyun Seo Woong Sik Jang In Hee Lee Hyung Joon Cha 《Applied microbiology》2005,71(9):5038-5043
Several fusion strategies have been developed for the expression and purification of small antimicrobial peptides (AMPs) in recombinant bacterial expression systems. However, some of these efforts have been limited by product toxicity to host cells, product proteolysis, low expression levels, poor recovery yields, and sometimes an absence of posttranslational modifications required for biological activity. For the present work, we investigated the use of the baculoviral polyhedrin (Polh) protein as a novel fusion partner for the production of a model AMP (halocidin 18-amino-acid subunit; Hal18) in Escherichia coli. The useful solubility properties of Polh as a fusion partner facilitated the expression of the Polh-Hal18 fusion protein (~33.6 kDa) by forming insoluble inclusion bodies in E. coli which could easily be purified by inclusion body isolation and affinity purification using the fused hexahistidine tag. The recombinant Hal18 AMP (~2 kDa) could then be cleaved with hydroxylamine from the fusion protein and easily recovered by simple dialysis and centrifugation. This was facilitated by the fact that Polh was soluble during the alkaline cleavage reaction but became insoluble during dialysis at a neutral pH. Reverse-phase high-performance liquid chromatography was used to further purify the separated recombinant Hal18, giving a final yield of 30% with >90% purity. Importantly, recombinant and synthetic Hal18 peptides showed nearly identical antimicrobial activities against E. coli and Staphylococcus aureus, which were used as representative gram-negative and gram-positive bacteria, respectively. These results demonstrate that baculoviral Polh can provide an efficient and facile platform for the production or functional study of target AMPs. 相似文献