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101.
Kim JS Romero R Tarca AL LaJeunesse C Han YM Kim MJ Suh YL Draghici S Mittal P Gotsch F Kusanovic JP Hassan S Kim CJ 《Journal of cellular and molecular medicine》2008,12(4):1317-1330
There is a difference in the susceptibility to inflammation between the umbilical vein (UV) and the umbilical arteries (UAs). This led us to hypothesize that there is an intrinsic difference in the pro-inflammatory response between UA and UV. Real-time quantitative RT-PCR and microarray analysis revealed higher expression of interleukin (IL)-1β and IL-8 mRNA in the UV and differential expression of 567 genes between the UA and UV associated with distinct biological processes, including the immune response. Differential expression of human leukocyte antigen (HLA)-DRA mRNA between the UA and UV was due to unexpected HLA-DR+ cells migrating via the umbilical vessels into Wharton's jelly, more frequently in the UV. A significant proportion of these cells co-expressed CD45 and type I pro-collagen, and acquired CD163 or α-smooth muscle actin immunoreactivity in Wharton's jelly. Migrating cells were also found in the chorionic and stem villous vessels. Furthermore, the extent of migration increased with progression of gestation, but diminished in intrauterine growth restriction (IUGR). The observations herein strongly suggest that circulating foetal fibrocytes, routing via umbilical and placental vessels, are a reservoir for key cellular subsets in the placenta. This study reports fibrocytes in the human umbilical cord and placenta for the first time, and a novel role for both circulating foetal cells and the umbilical vessels in placental development, which is deranged in IUGR. 相似文献
102.
Jun YJ Min JH Ji da E Yoo JH Kim JH Lee HJ Jeong B Sohn YS 《Bioorganic & medicinal chemistry letters》2008,18(24):6410-6413
A novel water soluble and biodegradable cyclotriphosphazene-paclitaxel conjugate was prepared by reacting 2'-succinyl paclitaxel with cyclotriphosphazenes bearing equimolar glycyl-L-lysine and methoxy poly(ethylene glycol) as side groups. The macromolecular conjugate was found to self-assemble in aqueous solution to form stable micelles with a mean hydrodynamic diameter of 24.7 nm and a low critical micelle concentration of 10 mg/L. The present conjugate exhibited lower than free paclitaxel but reasonably high in vitro cytotoxicity against selected human tumor cells due to their hydrolytic degradation in PBS solution. 相似文献
103.
Jong Wan Bae Seunghee Shin S. Mohan Raj Song Eun Lee Sun-Gu Lee Yong-Joo Jeong Sunghoon Park 《Biotechnology and Bioprocess Engineering》2008,13(1):69-76
A recombinant Escherichia coli (pBAB1) containing styrene monooxygenase (SMO) was developed for the conversion of styrene to enantiopure (S)-styrene oxide that is an important chiral building block in organic synthesis. The styAB genes encoding SMO was cloned into a multicopy plasmid under the tightly regulated promoter of bacterial l-arabinose operon which is inducible by l-arabinose. The recombinant showed that expression level of StyA protein and whole-cell SMO activities were varied depending
on the concentration of the inducer l-arabinose. The maximum SMO activity was 108 U/g cdw when the cells were induced with 0.2% l-arabinose. SDS-PAGE and Western blot analyses indicated that whole-cell SMO activity was strongly correlated with the expression
level of StyA protein. Organic-aqueous two-phase experiment could yield 50 mM enantiopure (S)-styrene oxide in organic phase in 18 h, but the recombinant SMO activity was unstable during the reaction. The expression
of styAB under the control of l-arabinose promoter was significantly repressed in the presence of glucose. 相似文献
104.
Apoptosis (programmed cell death) is a cellular self-destruction mechanism that is essential for a variety of biological events, such as developmental sculpturing, tissue homeostasis, and the removal of unwanted cells. Mitochondria play a crucial role in regulating cell death. Ca2+ has long been recognized as a participant in apoptotic pathways. Mitochondria are known to modulate and synchronize Ca2+ signaling. Massive accumulation of Ca2+ in the mitochondria leads to apoptosis. The Ca2+ dynamics of ER and mitochondria appear to be modulated by the Bcl-2 family proteins, key factors involved in apoptosis. The number and morphology of mitochondria are precisely controlled through mitochondrial fusion and fission process by numerous mitochondria-shaping proteins. Mitochondrial fission accompanies apoptotic cell death and appears to be important for progression of the apoptotic pathway. Here, we highlight and discuss the role of mitochondrial calcium handling and mitochondrial fusion and fission machinery in apoptosis. 相似文献
105.
Uluçkan O Eagleton MC Floyd DH Morgan EA Hirbe AC Kramer M Dowland N Prior JL Piwnica-Worms D Jeong SS Chen R Weilbaecher K 《Journal of cellular biochemistry》2008,104(4):1311-1323
Platelets contribute to the development of metastasis, the most common cause of mortality in cancer patients, but the precise role that anti-platelet drugs play in cancer treatment is not defined. Metastatic tumor cells can produce platelet alphaIIb beta3 activators, such as ADP and thromboxane A(2) (TXA(2)). Inhibitors of platelet beta3 integrins decrease bone metastases in mice but are associated with significant bleeding. We examined the role of a novel soluble apyrase/ADPase, APT102, and an inhibitor of TXA(2) synthesis, acetylsalicylic acid (aspirin or ASA), in mouse models of experimental bone metastases. We found that treatment with ASA and APT102 in combination (ASA + APT102), but not either drug alone, significantly decreased breast cancer and melanoma bone metastases in mice with fewer bleeding complications than observed with alphaIIb beta3 inhibition. ASA + APT102 diminished tumor cell induced platelet aggregation but did not directly alter tumor cell viability. Notably, APT102 + ASA treatment did not affect initial tumor cell distribution and similar results were observed in beta3-/- mice. These results show that treatment with ASA + APT102 decreases bone metastases without significant bleeding complications. Anti-platelet drugs such as ASA + APT102 could be valuable experimental tools for studying the role of platelet activation in metastasis as well as a therapeutic option for the prevention of bone metastases. 相似文献
106.
107.
Role of Arabidopsis CHL27 protein for photosynthesis, chloroplast development and gene expression profiling 总被引:1,自引:0,他引:1
Bang WY Jeong IS Kim DW Im CH Ji C Hwang SM Kim SW Son YS Jeong J Shiina T Bahk JD 《Plant & cell physiology》2008,49(9):1350-1363
In Chl biosynthesis, aerobic Mg-protoporphyrin IX monomethyl ester (MPE) cyclase is a key enzyme involved in the synthesis of protochlorophyllide a, and its membrane-bound component is known to be encoded by homologs of CHL27 in photosynthetic bacteria, green algae and plants. Here, we report that the Arabidopsis chl27-t knock-down mutant exhibits retarded growth and chloroplast developmental defects that are caused by damage to PSII reaction centers. The mutant contains a T-DNA insertion within the CHL27 promoter that dramatically reduces the CHL27 mRNA level. chl27-t mutant plants grew slowly with a pale green appearance, suggesting that they are defective in Chl biosynthesis. Chl fluorescence analysis showed significantly low photosynthetic activity in chl27-t mutants, indicating damage in their PSII reaction centers. The chl27-t mutation also conferred severe defects in chloroplast development, including the unstacking of thylakoid membranes. Microarray analysis of the chl27-t mutant showed repression of numerous nuclear genes involved in photosynthesis, including those encoding components of light-harvesting complex I (LHCI) and LHCII, and PSI and PSII, which accounts for the defects in photosynthetic activity and chloroplast development. In addition, the microarray data also revealed the significant repression of genes such as PORA and AtFRO6 for Chl biosynthesis and iron acquisition, respectively, and, furthermore, implied that there is cross-talk in the Chl biosynthetic pathway among the PORA, AtFRO6 and CHL27 proteins. 相似文献
108.
Kumar P Ban HS Kim SS Wu H Pearson T Greiner DL Laouar A Yao J Haridas V Habiro K Yang YG Jeong JH Lee KY Kim YH Kim SW Peipp M Fey GH Manjunath N Shultz LD Lee SK Shankar P 《Cell》2008,134(4):577-586
Evaluation of the therapeutic potential of RNAi for HIV infection has been hampered by the challenges of siRNA delivery and lack of suitable animal models. Using a delivery method for T cells, we show that siRNA treatment can dramatically suppress HIV infection. A CD7-specific single-chain antibody was conjugated to oligo-9-arginine peptide (scFvCD7-9R) for T cell-specific siRNA delivery in NOD/SCIDIL2rgamma-/- mice reconstituted with human lymphocytes (Hu-PBL) or CD34+ hematopoietic stem cells (Hu-HSC). In HIV-infected Hu-PBL mice, treatment with anti-CCR5 (viral coreceptor) and antiviral siRNAs complexed to scFvCD7-9R controlled viral replication and prevented the disease-associated CD4 T cell loss. This treatment also suppressed endogenous virus and restored CD4 T cell counts in mice reconstituted with HIV+ peripheral blood mononuclear cells. Moreover, scFvCD7-9R could deliver antiviral siRNAs to naive T cells in Hu-HSC mice and effectively suppress viremia in infected mice. Thus, siRNA therapy for HIV infection appears to be feasible in a preclinical animal model. 相似文献
109.
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
110.
Piperlonguminine (PL), an important component of Piper longum fruits, is known to exhibit anti-hyperlipidemic, antiplatelet and anti-melanogenic activities. Here, the anticoagulant activities of PL were examined by monitoring activatedpartial-thromboplastin-time (aPTT), prothrombin-time (PT), and the activities of thrombin and activated factor X (FXa). The effects of PL on the expressions of plasminogen activator inhibitor type 1 (PAI-1) and tissue-type plasminogen activator (t-PA) were also tested in tumor necrosis factor-α (TNF-α) activated HUVECs. The results showed that PL prolonged aPTT and PT significantly and inhibited the activities of thrombin and FXa. PL inhibited the generation of thrombin and FXa in HUVECs. In accordance with these anticoagulant activities, PL prolonged in vivo bleeding time and inhibited TNF-α induced PAI-1 production. Furthermore, PAI-1/t-PA ratio was significantly decreased by PL. Collectively, our results suggest that PL possesses antithrombotic activities and that the current study could provide bases for the development of new anticoagulant agents. [BMB Reports 2013; 46(10): 484-489] 相似文献