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81.
Hisako Sakiyama Kazuhiko Kaji Koichi Nakagawa Ken Nagino 《Cell biochemistry and function》1998,16(3):159-163
The first complement component C1s formed large aggregates with bFGF when bFGF and C1s were incubated at 37°C overnight. Under non-reducing conditions, a part of the aggregates did not penetrate into 5% polyacrylamide gel in the presence of SDS, and the rest penetrated into 5% gel but not into 12% gel. The aggregates were dissociated into monomers by reducing with 2-mercaptoethanol. Both active and inactive C1s formed aggregates with bFGF. In addition, a portion of bFGF was degraded by active C1s but not by inactive C1s. Aggregates were not formed when 2-mercaptoethanol (2 mM &base;) was added to the incubation mixture. After the incubation with C1s the growth-stimulating activity of bFGF was measured by using human umbilical vein endothelial cells (HUVEC) as indicator cells. The aggregate formation between C1s and bFGF significantly reduced the activity of bFGF. © 1998 John Wiley & Sons, Ltd. 相似文献
82.
Prolactin induces MFG-E8 production in macrophages via transcription factor C/EBPβ-dependent pathway
Aziz MM Ishihara S Rumi MA Mishima Y Oshima N Kadota C Moriyama I Li YY Rahman FB Otani A Oka A Ishimura N Kadowaki Y Amano Y Kinoshita Y 《Apoptosis : an international journal on programmed cell death》2008,13(5):609-620
The lactogenic hormone prolactin (PRL) regulates milk protein gene expression in mammary glands. To maintain homeostatic balance
in the body, milk fat globule epidermal growth factor 8 (MFG-E8) is vital for phagocytic clearance of apoptotic cells. We
investigated the effects of PRL on MFG-E8 expression in macrophages by evaluating its promoter function. Macrophages were
stimulated with PRL, and the expression of MFG-E8 was determined using real-time PCR and Western blotting. The role of MFG-E8
on phagocytosis of apoptotic cells in PRL-treated macrophages was assessed using microscopy, while the response of PRL to
MFG-E8 expression was evaluated using luciferase assay. Following treatment with PRL, significant up-regulations of the PRL
receptor and MFG-E8 were observed in macrophages, though PRL-treated macrophages more efficiently engulfed apoptotic cells.
The results of MFG-E8 promoter analysis showed considerable up-regulation of promoter activity in macrophages following PRL
treatment and results from mutation analysis of the MFG-E8 promoter suggested that the C/EBPβ binding site was responsible
for PRL-induced activation of the MFG-E8 promoter. C/EBPβ activity was found to be up-regulated in PRL-treated cells as revealed
by an electrophoretic mobility shift assay (EMSA). In conclusion, PRL is a potent inducer of MFG-E8 expression in macrophages,
while its effect is mediated by the presence of a responsive element in the MFG-E8 promoter. 相似文献
83.
Shin Iwamoto Norihisa Nishimichi Yoshiko Tateishi Yuko Sato Hiroyuki Horiuchi Shuichi Furusawa Tatsuya Sawamura Haruo Matsuda 《MABS-AUSTIN》2009,1(4):357-363
Lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (LOX-1) is the major receptor for oxidized LDL (oxLDL), and plays a key role in the pathogenesis of atherosclerosis and cardiovascular diseases. Monoclonal antibodies (mAbs) specific for human LOX-1 (hLOX-1) were generated by a phage display technique using chickens immunized with recombinant hLOX-1 (rhLOX-1). A total of 53 independent scFv clones reactive for rhLOX-1 were obtained. Of the 53 clones, 49 recognized the C-type lectin-like domain (CTL domain), which contributes to the binding of oxLDL. Of these, 45 clones inhibited oxLDL-binding with LOX-1. Furthermore, some of these clones cross-reacted with rabbit, pig and/or mouse LOX-1. For possible application as therapeutic agents in the future, two cross-reactive mAbs were re-constructed as chicken-human chimeric antibodies. The chimeric antibodies showed similar characteristics compared to the original antibodies, and inhibited oxLDL binding to LOX-1 expressed on CHO cells. The results obtained in this study indicate that anti-LOX-1 mAbs might be useful tools for functional analyses and development of therapeutic agents for cardiovascular indications such as atherosclerosis.Key words: LOX-1, oxLDL, chicken monoclonal antibody, chimeric antibody, neutralizing antibody 相似文献
84.
85.
The diffusion coefficient of the water component in a freeze-concentrated matrix is a useful parameter for predicting and
controlling the recrystallization rate of ice crystals in sugar solutions relevant to frozen desserts. Herein, application
of molecular dynamics (MD) for estimating the water diffusion coefficient in a freeze-concentrated matrix of sugar solutions
is described. Diffusion coefficients evaluated using MD with the optimized potentials for liquid simulations all atom force
field and water models of three types (simple point charge, simple point charge extended, and transferable intermolecular
potential-4 point) show a good positive linear relation with measured values, indicating that the MD methods used in this
study are useful for predicting differences in water diffusion coefficients in a sugar freeze-concentrated matrix. Furthermore,
similarly to measured values, the estimated diffusion coefficients show a good positive correlation with recrystallization
rates of ice crystals, which suggests that MD is useful to predict differences in recrystallization rates of ice crystals
in frozen sugar solutions. 相似文献
86.
Goh Nishitani Satoshi Nagai Chunlan Lian Sanae Sakiyama Akihiko Oohashi Kazuyoshi Miyamura 《Conservation Genetics》2009,10(3):713-715
The marine phytoplankton, Karenia mikimotoi, causes severe red tides which are associated with mass mortality of marine fish, and have expanded their distributions in
the coastal waters of western Japan. To assess the dispersal mechanism, a population genetic study using highly polymorphic
genetic markers is one of the crucial approaches. Here we developed 12 polymorphic microsatellite markers from K. mikimotoi. These loci provide a class of highly variable genetic markers, as the number of alleles ranged from 5 to 23, and the estimate
of gene diversity was from 0.551 to 0.933 across the 12 microsatellites. We consider these loci potentially useful for detailing
the genetic structure and gene flow among K. mikimotoi populations. 相似文献
87.
Huang CS Kawamura T Peng X Tochigi N Shigemura N Billiar TR Nakao A Toyoda Y 《Biochemical and biophysical research communications》2011,(2):253-258
Entry of enveloped viruses into cells is initiated by binding of their envelope glycoproteins (Envs) to cell surface-associated receptors. The Crimean-Congo hemorrhagic fever virus (CCHFV) has two Envs, Gn and Gc, with poorly understood role in binding to susceptible cells. We expressed codon optimized Gn and Gc, and identified independently folded soluble Env fragments, one of which (Gc residues 180–300) bound CCHFV susceptible cells supposedly by interacting with a putative receptor. This receptor binding domain (RBD) was used to identify its interacting partner by coimmunoprecipitation and mass spectrometry. Thus we identified the human cell surface nucleolin as a putative CCHFV entry factor. Nucleolin was expressed on all susceptible cells tested but not on the surface of cells resistant to CCHFV infection. Further studies are needed to explore the nucleolin function as a plausible CCHFV receptor and the molecular mechanisms of the Gc-nucleolin interactions. The identification of the CCHFV RBD and its binding partner could provide novel targets for therapy and tools for prevention as well as more complete understanding of the mechanisms of CCHFV entry and pathogenesis. 相似文献
88.
Fujii Y Norihisa K Fujii T Aritoku Y Kagawa Y Sallam KI Johdo O Arisawa A Tamura T 《Biochemical and biophysical research communications》2011,(1):511-516
The novel plasmid vector (pTAOR4-Rev) suitable for gene expression in actinomycete strains of Pseudonocardia autotrophica was constructed from 2 P. autotrophica genetic elements, the novel replication origin and the acetone-inducible promoter. The replication origin was isolated from the endogenous plasmid of strain DSM 43082 and the acetone-inducible promoter was determined by analysis of the upstream region of an acetaldehyde dehydrogenase gene homologue in strain NBRC 12743. P. autotrophica strains transformed with pTAOR4-P450, carrying a gene for cytochrome P450 monooxygenase, expressed P450 from the acetone-inducible promoter, as verified by SDS–PAGE and spectral analysis. The biotransformation test of acetone-induced resting cells prepared from a strain of P. autotrophica carrying pTAOR4 that harbors a compactin (CP)-hydroxylating P450 gene revealed 3.3-fold increased production of pravastatin (PV), a drug for hypercholesterolemia. Biotransformation of CP by the same strain in batch culture yielded PV accumulation of 14.3 g/l after 100 h. The expression vector pTAOR4-Rev and its function-enhancing derivatives provide a versatile approach to industrial biotransformation by Pseudonocardia strains, which can be good hosts for P450 monooxygenase expression. 相似文献
89.
A dinickel(II) complex [Ni2(sym-hmp)2](BPh4)2·3.5DMF·0.5(2-PrOH) (1) was synthesized with a dinucleating ligand, 2,6-bis[(2-hydroxyethyl)methylaminomethyl]-4-methyl-phenol [H(sym-hmp)]. The complex 1 (C90H118.50B2N7.50Ni2O10) crystallized in the triclinic space group with dimensions a = 14.7446(4) Å, b = 15.4244(4) Å, c = 18.7385(6) Å, α = 86.9495(9)°, β = 76.7263(10)°, γ = 86.5370(8)°, and V = 4136.8(2) Å3 and with Z = 2; this is isomorphous to a previous cobalt(II) complex [Co2(sym-hmp)2](BPh4)2. Single-crystal X-ray analysis revealed a bis(μ-phenoxo)dinickel(II) core structure containing two distorted octahedral nickel(II) ions of C2 symmetry. The order of the coordination bond lengths is Ni-O(phenoxo) < Ni-O(hydroxy) < Ni-N. The electronic spectrum of 1 was typical for the octahedral nickel(II) complexes, but the axial elongation and the C2-twist of the equatorial plane were found after a detailed analysis. The bond angles obtained by the electronic spectrum agreed with the crystallographically obtained bond angles within 2.3°. The order of the AOM parameters was eσ,O(phenoxo) > eσ,O(hydroxy) > eσ,N, which was consistent with the order of the coordination bond lengths. Magnetic susceptibility data for 1 were fitted well with the parameters 2J = −69.7 cm−1, D = 0.00 cm−1, g = 2.17, and TIP = 265 × 10−6 cm3 mol−1. The result indicates significant antiferromagnetic exchange interaction and negligible zero-field splitting, while the isostructural cobalt(II) complex showed an anisotropic behavior. 相似文献
90.
Shimoda H Ninomiya K Nishida N Yoshino T Morikawa T Matsuda H Yoshikawa M 《Bioorganic & medicinal chemistry letters》2003,13(2):223-228
The methanolic extract from the leaves of artichoke (Cynara scolymus L.) was found to suppress serum triglyceride elevation in olive oil-loaded mice. Through bioassay-guided separation, sesquiterpenes (cynaropicrin, aguerin B, and grosheimin) were isolated as the active components together with new sesquiterpene glycosides (cynarascolosides A, B, and C). The oxygen functional groups at the 3- and 8-positions and exo-methylene moiety in alpha-methylene-gamma-butyrolactone ring were found to be essential for the anti-hyperlipidemic activity of guaiane-type sesquiterpene. In addition, inhibition of gastric emptying was shown to be partly involved in anti-hyperlipidemic activity. 相似文献