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71.
Lyons C Beharry K Akmal Y Attenello F Nageotte MP 《Prostaglandins & other lipid mediators》2003,70(3-4):317-329
We examined and compared the in vitro effects of misoprostol (synthetic prostaglandin E1 (PGE1) analogue) on prostaglandin E2 (PGE2) secretion and EP3 receptor mRNA expression in the pregnant rat myometrium and cervix at 19 days gestation. Myometrial and cervical tissue samples were exposed to media with or without misoprostol (50 or 100 pg/ml) and incubated for 15 and 30 min, and 1, 3, 6, 12, and 24 h. Media and tissue samples were collected for quantification of PGE2 and mRNA expression of rEP3alpha and rEP3beta receptor, respectively. PGE2 secretion increased (P < or = 0.05) in the myometrium exposed to 50 and 100 pg/ml misoprostol. Cervical PGE2 secretion increased following exposure to the 100 pg/ml dose only. In the myometrium, 50 and 100 pg/ml misoprostol induced elevations in rEP3alpha and rEP3beta receptor mRNA expression. rEP3alpha and rEP3beta receptor mRNA expression in the cervix was not different from controls. These data demonstrate that the EP3 receptor is differentially expressed in the myometrium and cervix in response to misoprostol. This may account for the ability of misoprostol to stimulate the myometrium when administered for cervical ripening. 相似文献
72.
Johnson KR Lane PW Cook SA Harris BS Ward-Bailey PF Bronson RT Lyons BL Shultz LD Davisson MT 《Genomics》2003,81(1):6-14
In the outcrossing of a new recessive mouse mutation causing hair loss, a new wavy-coated phenotype appeared. The two distinct phenotypes were shown to be alternative manifestations of the same gene mutation and attributable to a single modifier locus. The new mutation, curly bare (cub), was mapped to distal Chr 11 and the modifier (mcub) was mapped to Chr 5. When homozygous for the recessive mcub allele, cub/cub mice appear hairless. A single copy of the dominant Mcub allele confers a full, curly coat in cub/cub mice. Reciprocal transfer of full-thickness skin grafts between mutant and control animals showed that the skin phenotype was tissue autonomous. The hairless cub/cub mcub/mcub mice show normal contact sensitivity responses to oxazolone. The similarity of the wavy coat phenotype to those of Tgfa and Egfr mutations and the map positions of cub and mcub suggest candidate genes that interact in the EGF receptor signal transduction pathway. 相似文献
73.
Turgeon NA Banuelos SJ Shultz LD Lyons BL Iwakoshi N Greiner DL Mordes JP Rossini AA Appel MC 《Experimental biology and medicine (Maywood, N.J.)》2003,228(9):1096-1104
Small animal models with the capacity to support engraftment of a functional human immune system are needed to facilitate studies of human alloimmunity. In the present investigation, non-obese diabetic (NOD) severe combined immunodeficient (scid) beta2-microglobulin-null (B2mnull) mice engrafted with human peripheral blood lymphocytes (hu-PBL-NOD-scid B2mnull mice) were used as in vivo models for studying human skin allograft rejection. Hu-PBL-NOD-scid B2mnull mice were established by injection of human spleen cells or PBLs and transplanted with full-thickness allogeneic human skin. Human cell engraftment was enhanced by injection of anti-mouse CD122 antibody. The respective contributions of human CD4+ and CD8+ cells in allograft rejection were determined using depleting antibodies. Human skin grafts on unmanipulated NOD-scid B2mnull mice uniformly survived but on chimeric hu-PBL-NOD-scid B2mnull mice exhibited severe immune-mediated injury that often progressed to complete rejection. The alloaggressive hu-PBLs did not require prior in vitro sensitization to elicit targeted effector cell activity. Extensive mononuclear cell infiltration directed towards human-origin endothelium was associated with thrombosis and fibrin necrosis. No evidence of graft-versus-host disease was detected. Either CD4+ or CD8+ T cells may mediate injury and alloimmune rejection of human skin grafts on hu-PBL-NOD-scid B2mnull mice. It is proposed that Hu-PBL-NOD-scid B2mnull mice engrafted with human skin will provide a useful model for analysis of interventions designed to modulate human allograft rejection. 相似文献
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75.
Lakes in Taylor Valley, southern Victoria Land,Antarctica, are unusual in that they areperennially covered by a 3–5 m thick ice layer.Previous work on gas concentrations in theselakes has shown that the surface waters aresupersaturated with respect to O2,N2O, as well as the noble gases. Our datashow that the dissolved CO2 (CO2(aq))concentrations, calculated from pH andCO2, can be highly undersaturatedat shallow depths of the lakes. CO2partial pressure values (pCO2) are as lowas 10–4.3 atm and 10–4.2 atm in theeast and west lobes of Lake Bonney,respectively, and 10–3.8 atm in LakeHoare. CO2(aq) depletion occurred only inthe uppermost part of the water column, inassociation with elevated primary productivity(PPR). The upward diffusion of CO2(aq)from the aphotic zone, and the annual input ofCO2 via glacial meltwater can notreplenish the amount of CO2(aq) annuallylost to primary productivity in the uppermostmeters of the water column. Calcification is alimited source of CO2(aq), since the lakesare undersaturated with respect to calcitethrough portions of the austral summer.Preliminary respiration rates have been used toobtain an annual inorganic carbon balance.Further down in the water column, at the sitesof the deep-water maximum in primary production(PPRmax), which in Lakes Bonney andFryxell is associated with nutrient gradients,CO2(aq) is not undersaturated. A largeupward flux from CO2-supersaturatedaphotic waters provides a surplus ofCO2(aq) at the PPRmax. Lake Fryxell,unlike the other lakes, is supersaturated withCO2(aq) throughout the entire water column. 相似文献
76.
The copper transport protein Atox1 promotes neuronal survival 总被引:5,自引:0,他引:5
Kelner GS Lee M Clark ME Maciejewski D McGrath D Rabizadeh S Lyons T Bredesen D Jenner P Maki RA 《The Journal of biological chemistry》2000,275(1):580-584
Atox1, a copper transport protein, was recently identified as a copper-dependent suppressor of oxidative damage in yeast lacking superoxide dismutase. We have previously reported that Atox1 in the rat brain is primarily expressed in neurons, with the highest levels in distinct neuronal subtypes that are characterized by their high levels of metal, like copper, iron, and zinc. In this report, we have transfected the Atox1 gene into several neuronal cell lines to increase the endogenous level of Atox1 expression and have demonstrated that, under conditions of serum starvation and oxidative injury, the transfected neurons are significantly protected against this stress. This level of protection is comparable with the level of protection seen with copper/zinc superoxide dismutase and the anti-apoptotic gene bcl-2 that had been similarly transfected. Furthermore, neuronal cell lines transfected with a mutant Atox1 gene, where the copper binding domain has been modified to prevent metal binding, do not afford protection against serum starvation resulting in apoptosis. Therefore, Atox1 is a component of the cellular pathways used for protection against oxidative stress. 相似文献
77.
78.
Cecilia PC Soh Alastair SR Donald James Feeney Walter TJ Morgan Winifred M Watkins 《Glycoconjugate journal》1989,6(3):319-332
The tetrasaccharides GalNAcß1-4[NeuAc2-3]Galß1-4Glc and GalNAcß1-4[NeuAc2-3]Galß1-4GlcNAc were synthesised by enzymic transfer of GalNAc from UDP-GalNAc to 3-sialyllactose (NeuAc2-3Galß1-4Glc) and 3-sialyl-N-acetyllactosamine (NeuAc2-3Galß1-4GlcNAc). The structures of the products were established by methylation and1H-500 MHz NMR spectroscopy. In Sda serological tests the product formed with 3-sialyl-N-acetyllactosamine was highly active whereas that formed with 3-sialyllactose had only weak activity. 相似文献
79.
Tyagarajan S Chakravarty PK Zhou B Taylor B Eid R Fisher MH Parsons WH Wyvratt MJ Lyons KA Klatt T Li X Kumar S Williams B Felix J Priest BT Brochu RM Warren V Smith M Garcia M Kaczorowski GJ Martin WJ Abbadie C McGowan E Jochnowitz N Weber A Duffy JL 《Bioorganic & medicinal chemistry letters》2010,20(24):7479-7482
A series of novel biphenyl pyrazole dicarboxamides were identified as potential sodium channel blockers for treatment of neuropathic pain. Compound 20 had outstanding efficacy in the Chung rat spinal nerve ligation (SNL) model of neuropathic pain. 相似文献
80.