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991.
Aminopeptidase N/CD13 induces angiogenesis through interaction with a pro-angiogenic protein, galectin-3 总被引:2,自引:0,他引:2
Yang E Shim JS Woo HJ Kim KW Kwon HJ 《Biochemical and biophysical research communications》2007,363(2):336-341
Aminopeptidase N/CD13 is an endothelial cell surface ectoenzyme involved in one of the initial steps of angiogenesis. However, little is known how APN induces angiogenesis in endothelial cells. Using human cDNA library-encoding phage display biopanning method, we here identified a galactoside-specific lectin family protein, galectin-3, as an interacting protein of APN. Galectin-3 specifically binds to APN both in vitro and in human umbilical vein endothelial cells (HUVECs) in a carbohydrate recognition-dependent manner. Immunohistochemical analysis demonstrates that both APN and galectin-3 are exclusively coexpressed during the angiogenic stage of mouse forebrain development. Finally, exogenous addition of galectin-3 into HUVECs induced angiogenesis in an APN-dependent manner, implying that APN is a crucial mediator of galectin-3-induced angiogenesis in endothelial cells. 相似文献
992.
993.
Gyoo Yeol Jung Jung Rae Kim Hyun Ok Jung Ji-Young Park Sunghoon Park 《Biotechnology letters》1999,21(10):869-873
A new bacterium, Citrobacter sp. Y19, catalyzing the water-gas shift reaction was isolated from an anaerobic wastewater sludge digester. It grew aerobically with a high specific growth rate of 0.7 h–1 in a mineral salt medium supplemented with yeast extract and Bacto-tryptone, and produced H2 under anaerobic conditions after the cells were transferred to tryptone-deleted medium. The maximum H2 production rate was 33 mmol H2 g–1 cell h, which was maintained for about 200 h. This is the first report on a chemoheterotrophic bacterium which utilizes CO with the production of H2 and CO2. 相似文献
994.
Rainbow trout Oncorhynchus mykiss injected intramuscularly with isometamidium chloride (0.01 or 0.1 mg kg-1) at 3 wk post-infection and given a booster 2 wk later had significantly lower parasitaemias than infected controls. Packed cell volume increased after treatment and remained higher than in infected controls. The concentration of isometamidium in plasma was highest at 2 wk after injection and then declined. An intramuscular dose of 1.0 mg kg-1 of isometamidium chloride at 1, 2 and 3 wk postinfection (preclinical) significantly reduced the parasitaemia in rainbow trout 2 wk after treatment. A booster at 9 wk postinfection (chronic disease phase) reduced the parasitaemia further in all fish. The packed cell volume in these fish was higher than in infected controls. Treatment at 5, 6, and 7 wk postinfection (acute disease) had no effects and parasitaemias in treated fish were higher than in infected controls; also, anti-Cryptobia salmositica antibodies and titres of complement-fixing antibody were higher in these than in infected controls. Incubation of immune plasma or complement with isometamidium for 3 h did not affect the lytic titres of complement-fixing antibodies nor rainbow trout complement. 相似文献
995.
George T. Cicila Carl Choi Howard Dene Soon Jin Lee John P. Rapp 《Mammalian genome》1999,10(2):112-116
Interval mapping was used to identify putative quantitative trait loci (QTL) for blood pressure and cardiac mass on Chromosome
(Chr) 3 in F1(S × R) × S population of 150 rats raised on an 8% NaCl diet. Two genetic markers 95.7 cM apart, D3Wox3 and D3Mco5 (tightly linked to Edn3), showed ``suggestive' linkage to blood pressure (LOD = 2.0 and 1.8 respectively). In addition, D3Wox3 showed ``suggestive' linkage to heart weight (LOD = 2.5), and D3Mco5 showed ``suggestive' linkage to body weight–adjusted heart weight (LOD = 2.1). Congenic rats (designated S.R-Edn3) were
constructed by introgressing the R-rat Edn3 allele (and flanking loci) into the S strain. On a 2% NaCl diet, S.R-Edn3 rats had lower blood pressure (21.4 mm Hg, P= 0.0005) and heart weight (59 mg, P= 0.0038) compared with S rats, confirming the existence of a blood pressure QTL on Chr 3 near Edn3 even though QTL linkage analysis of blood pressure did not achieve stringent statistical criteria for significance. The results
of the congenic experiment and the large distance between the two putative QTL suggest the presence of at least two independent
blood pressure/cardiac mass QTL detectable on Chr 3 in the Dahl rat model of genetic hypertension.
Received: 24 April 1998 / Accepted: 29 September 1998 相似文献
996.
Sang Hyeon Kang Sang Taek Jung Taek Jin Kang Ryang Guk Kim Sang Hyuk Suh Ji Hyoung Woo Eun Yeol Lee Cha Yong Choi 《Biotechnology Techniques》1999,13(11):761-764
Each of the four nucleotides (A, C, G and T) was introduced as the base following the stop codon to investigate the effect of this fourth base on translational termination efficiency during the heterologous expression of human erythropoietin (hEPO) in E. coli. The efficiency of peptide chain termination in E. coli was markedly dependent on the fourth base. The choice of the fourth base was crucial to prevent the expression of undesirable proteins due to the translational infidelity such as frameshifting and stop codon read-through, and translational termination efficiency could be improved with adenosine as the fourth base. 相似文献
997.
Subculture of primary normal human oral keratinocytes (NHOK) results in terminal differentiation, leading to cell death. To investigate whether the subculture-induced death of NHOK is due to apoptosis, we studied transferase-mediated dUTP nick end labeling (TUNEL)-positive cells, DNA fragmentation, and expression of several apoptosis-associated genes from NHOK with different passage numbers. We also determined the effect of transforming growth factor beta1 (TGF-beta1) on the induction of apoptosis in NHOK. We were able to subculture primary NHOK up to the fifth passage, at which point cells showed morphological features of differentiation. Appearance of DNA fragmentation concurrently occurred with an increase in the number of TUNEL-positive cells with higher passage numbers. The level of cellular p53 proteins was gradually decreased by the continued passage of cells, whereas the levels of intracellular and secreted TGF-beta and phospholipase C-gamma1 (PLC-gamma1) were significantly elevated by serial subculture. Exogenous TGF-beta1 also induced differentiation and apoptosis of proliferating NHOK. These data indicate that terminal differentiation of NHOK is associated with apoptosis, which is, in part, linked to elevated cellular levels of TGF-beta and PLC-gamma1. 相似文献
998.
Subculture of primary normal human oral keratinocytes (NHOK) results in terminal differentiation, leading to cell death. To investigate whether the subculture-induced death of NHOK is due to apoptosis, we studied transferase-mediated dUTP nick end labeling (TUNEL)-positive cells, DNA fragmentation, and expression of several apoptosis-associated genes from NHOK with different passage numbers. We also determined the effect of transforming growth factor β1 (TGF-β1) on the induction of apoptosis in NHOK. We were able to subculture primary NHOK up to the fifth passage, at which point cells showed morphological features of differentiation. Appearance of DNA fragmentation concurrently occurred with an increase in the number of TUNEL-positive cells with higher passage numbers. The level of cellular p53 proteins was gradually decreased by the continued passage of cells, whereas the levels of intracellular and secreted TGF-β and phospholipase C-γ1 (PLC-γ1) were significantly elevated by serial subculture. Exogenous TGF-β1 also induced differentiation and apoptosis of proliferating NHOK. These data indicate that terminal differentiation of NHOK is associated with apoptosis, which is, in part, linked to elevated cellular levels of TGF-β and PLC-γ1. 相似文献
999.
Estimates of sperm sex chromosome disomy and diploidy rates in a 47,XXY/46,XY mosaic Klinefelter patient 总被引:6,自引:0,他引:6
A 47,XXY/46,XY male was investigated for the incidence of aneuploidy in sperm sex chromosomes using a three-colour X/Y/18
fluorescence in situ hybridisation (FISH) protocol. A total of 1701 sperm nuclei were analysed. The ratio of X-bearing to
Y-bearing sperm did not differ from the expected 1 : 1 ratio although there were more 23,Y sperm than 23,X sperm (844 vs 795).
There was a significantly increased proportion of disomy XY and XX sperm compared with normal controls (0.41% vs 0.10%, P < 0.001 and 0.29% vs 0.04%, P < 0.01). However, the incidence of YY sperm was similar to the controls (0.06% vs 0.02%). The diploidy rate was also significantly
increased (1.7% vs 0.13%, P < 0.0001), as was disomy 18 (0.71% vs 0.01%) and 25,XXY (0.47% vs 0%). The results support the hypothesis that some 47,XXY
cells are able to undergo meiosis and produce mature spermatozoa. Patients with mosaic Klinefelter syndrome with severe oligozoospermia
have significantly elevated incidences of disomy XY and XX sperm and may be at a slightly increased risk of producing 47,XXX
and 47,XXY offspring. Additionally, they may be at risk of producing offspring with autosomal trisomies. Hence, patients with
Klinefelter mosaicism scheduled for intracytoplasmic sperm injection intervention should first undergo FISH analysis of their
sperm to determine their risk.
Received: 16 November 1998 / Accepted: 16 February 1999 相似文献
1000.
Soo Woong Lee Hee Woo Lee Hyun Jae Chung Young-A Kim Yeon Jeong Kim Yoonsoo Hahn Jae Hoon Chung Young Shik Park 《FEMS microbiology letters》1999,176(1):169-176
The biosynthetic pathway for the pteridine moiety of cyanopterine, as well as tetrahydrobiopterine, has been investigated in Synechocystis sp. PCC 6803. Open reading frames slr0426, slr1626, slr0078 and sll0330 of the organism putatively encoding GTP cyclohydrolase I, dihydroneopterine aldolase, 6-pyruvoyltetrahydropterine synthase and sepiapterine reductase, respectively, have been cloned into T7-based vectors for expression in Escherichia coli. The recombinant proteins have been purified to homogeneity and demonstrated to possess expected genuine activities except that of sll0330. Our result is the first direct evidence for the functional assignment of the open reading frames in Synechocystis sp. PCC 6803. Furthermore, the 6-pyruvoyltetrahydropterine synthase gene is demonstrated for the first time in prokaryotes. Based on the result, biosynthesis of cyanopterine is discussed. 相似文献