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141.
G. Gradl P. Grandison E. Lindridge Y. Wang J. Watson F. Rudert 《Apoptosis : an international journal on programmed cell death》1996,1(2):131-140
Different CD95 (Fas/APO-1) isoforms and phosphory lated CD95 species were identified in human T and B cell lines. We had shown
previously that the CD95 intracellular domain (IC), expressed as a glutathione S-transferase (GST) fusion protein in murine
L929 fibroblasts, was phosphorylatedin vivo. GST-CD95IC was phosphorylatedin vitro by a kinase present in extracts from the human lymphocytic cell lines Jurkat and MP-1 and from murine L929 cells. Phosphoamino
acid analysis indicated that phosphorylation occurred at multiple threonine residues and also at tyrosine (Tyr232 and Tyr291)
and serine. Amino acids 191 to 275 of CD95 were sufficient for phosphorylation at threonine, tyrosine and serine and also
mediated interaction with a 35 kDa cellular protein. Immuno-precipitation of CD95 and chemical cross-linking revealed CD95-associated
proteins of approximately 35, 45 and 75 kDa. GST-CD95IC affinity chromatography detected binding of the 35 and 75 kDa protein
species. The 75 kDa species may correspond to the CD95-associated proteins RIP or FAF1 and the 35 kDa protein may represent
a TRADD analogue. These data indicate that several cellular proteins interact with CD95, possibly in a multi-protein complex,
and that a kinase activity is associated with CD95 not onlyin vitro but alsoin vivo. Therefore, receptor phosphorylation may play a role in CD95 signal transduction.
This work was in part supported by a grant from the Health Research Council of New Zealand (to JW). 相似文献
142.
K. Clifford R. Rai H. Watson S. Franks L. Regan 《BMJ (Clinical research ed.)》1996,312(7045):1508-1511
OBJECTIVE--To determine whether prepregnancy pituitary suppression of luteinising hormone secretion with a luteinising hormone releasing hormone analogue improves the outcome of pregnancy in ovulatory women with a history of recurrent miscarriage, polycystic ovaries, and hypersecretion of luteinising hormone. DESIGN--Randomised controlled trial. SETTING--Specialist recurrent miscarriage clinic. SUBJECTS--106 women with a history of three or more consecutive first trimester miscarriages, polycystic ovaries, and hypersecretion of luteinising hormone. INTERVENTIONS--Women were randomised before conception to receive pituitary suppression with a luteinising hormone releasing hormone analogue followed by low dose ovulation induction and luteal phase progesterone (group 1) or were allowed to ovulate spontaneously and then given luteal phase progesterone alone or luteal phase placebo alone (group 2). No drugs were prescribed in pregnancy. MAIN OUTCOME MEASURES--Conception and live birth rates over six cycles. RESULTS--Conception rates in the pituitary suppression and luteal phase support groups were 80% (40/50 women) and 82% (46/56) respectively (NS). Live birth rates were 65% (26/40) and 76% (35/46) respectively (NS). In the luteal phase support group there was no difference in the outcome of pregnancy between women given progesterone and those given placebo pessaries. Live birth rates from an intention to treat analysis were 52% (26/50 pregnancies) in the group given pituitary suppression and 63% (35/56) in the controls (NS). CONCLUSIONS--Prepregnancy suppression of high luteinising hormone concentrations in ovulatory women with recurrent miscarriage and hypersecretion of luteinising hormone does not improve the outcome of pregnancy. The outcome of pregnancy without pituitary suppression is excellent. 相似文献
143.
Ved Malik Mark B. Watson Russell L. Malmberg 《Journal of plant biochemistry and biotechnology.》1996,5(2):109-112
A partial cDNA clone encoding ornithine decarboxylase (ODC) has been isolated and sequenced from Nicotiana tabaccum. This 961 by long cDNA contained an open reading frame in only one of the six possible frames. Sequence comparisons have shown it to be very similar with other ODCs, and most similar to that from Datura. The present sequence is a partial sequence containing only 3′ half of the cDNA. 相似文献
144.
Fiona Watson 《Methods (San Diego, Calif.)》1996,9(3):578-590
Stimulation of neutrophils with a variety of stimuli can result in the activation of phospholipases A2, C, or D with the resultant hydrolysis of plasma membrane phospholipids and the formation of important second messenger molecules. In the neutrophil, the activities of these phospholipases have been implicated in the processes of both stimulating and maintaining oxidase activation. In this review, some of the methods currently used to measure the products of phospholipase activation in the neutrophil are described, along with the possible role of their products in reactive oxidant production by the neutrophil NADPH oxidase. 相似文献
145.
146.
Aspects of the phylogeny of Platyhelminthes based on 18S ribosomal DNA and protonephridial ultrastructure 总被引:2,自引:2,他引:0
DNA studies of 23 taxa (20 platyhelminths, 1 nemertean, Homo and Artemia) and electron-microscopic studies of the protonephridia of many platyhelminths (supported by some additional ultrastructural data) have led to the following conclusions: the Neodermata are monophyletic; Temnocephalida and Dalyelliida form one clade and are not the primitive sister group of the Neodermata; Gyrocotylidea, Amphilinidea and Eucestoda form one monophylum; Pterastericolidae and Umagillidae are dalyelliids and not the sister group of the Neodermata; and Proseriata are unlikely to be closely related with the Tricladida. A large taxon consisting of the Proseriata and some other turbellarians may represent the sister group of the Neodermata. 相似文献
147.
Observations on temporary waters in northwestern Australia 总被引:3,自引:1,他引:2
148.
149.
150.
The effects of calystegines isolated from edible fruits and vegetables on mammalian liver glycosidases 总被引:1,自引:0,他引:1
Asano Naoki; Kato Atsushi; Matsui Katsuhiko; Watson Alison A.; Nash Robert J.; Molyneux Russell J.; Hackett Lucy; Topping Joanna; Winchester Bryan 《Glycobiology》1997,7(8):1085-1088
The polyhydroxylated nortropane alkaloids called calyste-ginesoccur in many plants of the Convolvulaceae, Solanaceae, andMoraceae families. Certain of these alkaloids exhibit potentinhibitory activities against glycosidases and the recentlydemonstrated occurrence of calystegines in the leaves, skins,and sprouts of potatoes (Solatium tuberosum), and in the leavesof the eggplant (S.melongena), has raised concerns regardingthe safety of these vegetables in the human diet. We have surveyedthe occurrence of calystegines in edible fruits and vegetablesof the families Convolvulaceae, Solanaceae, and Moraceae byGC-MS. Calystegines A3, B1, B2, and C1 were detected in allthe edible fruits and vegetables tested; sweet and chili peppers,potatoes, eggplants, tomatoes, Physalis fruits, sweet potatoes,and mulberries. Calystegines B1 and C1 were potent competitiveinhibitors of the bovine, human, and rat β-glucosidaseactivities, with K1 values of 150, 10, and 1.9 µM, respectivelyfor B1 and 15,1.5, and 1 µM, respectively, for C1. CalystegineB2 was a strong competitive inhibitor of the -galactosidaseactivity in all the livers. Human β-xylosidase was inhibitedby all four nortropanes, with calystegine C1 having a K1 of0.13 µM. Calystegines A3 and B2 selectively inhibitedthe rat liver β-glucosidase activity. The potent inhibitionof mammalian β-glucosidase and -galactosidase activitiesin vitro raises the possibility of toxicity in humans consuminglarge amounts of plants that contain these compounds. edible plants calystegines glycosidase inhibitors bovine, human, and rat liver 相似文献