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31.
Modulation of implantation-associated integrin expression but not uteroglobin by steroid hormones in an endometrial cell line 总被引:2,自引:0,他引:2
Widra EA; Weeraratna A; Stepp MA; Stillman RJ; Patierno SR 《Molecular human reproduction》1997,3(7):563-568
In order to test the hypothesis that integrin and uteroglobin (UG)
expression in cultured endometrial cells are affected by hormone treatment,
Ishikawa-CH endometrial cancer cells were cultured and exposed to
oestradiol or oestradiol and progesterone regimens and assayed using
immunohistochemistry. We evaluated the intensity of immunohistochemical
staining for the integrin monomers alpha(v) and beta1, the dimers
alpha(v)beta3 and alpha(v)beta6, and for the secretory protein uteroglobin
under various experimental conditions. Cells grown in control media stained
positively for the integrin monomers alpha(v) and beta1, the dimer
alpha(v)beta3, and for UG. Oestradiol and sequential
oestradiol/progesterone reversibly suppressed staining for the dimer
alpha(v)beta3. Hormone treatment had no effect on the staining of the beta1
and alpha(v) monomers or UG. The alpha(v)beta6 dimer antibody did not stain
under any experimental treatment conditions. These data indicate that
expression of the integrin complex alpha(v)beta3 is reversibly suppressed
by oestradiol in Ishikawa cells and that these cells may be a good model
for studying hormone-driven molecular changes in endometrium.
相似文献
32.
羽叶三七叶中甙类成分的研究 总被引:3,自引:0,他引:3
从羽叶三七叶中分离到十三种甙类成分,经FAB-MS,13CNMR谱,双照射1HN-MR谱,1H-1H COSY谱及与标准品直接对照,证明十一种为已知化合物,分别为人参皂甙F1(Ⅰ),F2(Ⅱ),F3(Ⅲ),Rg2(Ⅳ),Ra(Ⅴ),Rd(Ⅵ),Rb1(Ⅷ),Rb3(Ⅷ),24(S)-假人参甙F11(Ⅸ),人参黄酮(Ⅹ)和珠子参甙F1(Ⅺ);另外两种为新的达玛烷型皂甙,命名为羽叶三七甙F1(Ⅻ)和F2(ⅫⅠ),并确定其化学结构。同时修正珠子参甙F3的结构。进一步阐明人参黄酮甙结构中的两个糖的连接方式。 相似文献
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Wallerian degeneration in the corticospinal tract was demonstrated by magnetic resonance (MR) imaging in a patient with Schilder disease. The histochemical stages of myelin breakdown that allow its demonstration by MR imaging are reviewed. 相似文献
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We developed a mouse monoclonal antibody (MoAb 115-21) to human high- molecular-weight kininogen (HK) that recognizes its prekallikrein binding site (residues 565 through 595 of HK). The corresponding synthesized 31-amino acid peptide (peptide IV) was recently shown to retain native HK's prekallikrein binding property. The same peptide bound factor XI also, although less avidly. Our MoAb recognizes purified HK, peptide IV, and the light chain moiety of HK (where the peptide IV resides), as shown by enzyme-linked immunosorbent assay (ELISA) and Western blotting experiments. The apparent dissociation constant for the HK and MoAb 115-21 interaction was 2.2 nmol/L. It does not recognize low-molecular-weight kininogen (LK) with which HK shares its heavy chain moiety or any antigens in human plasma congenitally deficient in kininogens. The binding of MoAb 115-21 to purified light chain of HK was competitively inhibited by peptide IV. In addition, the antibody inhibits HK-dependent clotting activity of normal human plasma and dextran sulfate-mediated activation of prekallikrein in plasma and retards cleavage of HK in normal plasma after contact activation with dextran sulfate. Also, purified Fab fragments of MoAb 115-21 inhibited the HK-dependent coagulant activity and dextran sulfate-mediated prekallikrein activation in normal plasma. Since the kd for HK-MoAb 115- 21 interaction is ten times lower than that of HK-prekallikrein, our data suggest that binding of MoAb 115-21 to HK's peptide IV site increases the free prekallikrein concentration in plasma and thus results in the decreased efficiency of factor XIIa-mediated activation of prekallikrein. Decreased levels of kallikrein thus formed may be responsible for the inhibition of HK-dependent clotting activity and the decrease in rate and extent of HK cleavage in normal plasma on contact activation with dextran sulfate. MoAb 115-21 may thus prove very useful, especially with its high affinity for HK, in further delineation of the role of HK and prekallikrein in contact activation and kinin-related human pathology. 相似文献