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Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
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CP Schaecher KA Groesch 《American journal of reproductive immunology (New York, N.Y. : 1989)》2006,55(6):405-405
Background: Control of mRNA stability is an essential regulatory process in eukaryotic gene expression. HuR, a 3'UTR mRNA binding protein, can protect AU-rich mRNA from degradation in response to stresses. PlGF, an angiogenic growth factor, contains two consensus AU-rich sites suggesting that under normal conditions HuR may protect PlGF mRNA from degradation. Trophoblast expression of PlGF is significantly decreased in preeclampsia and by hypoxia in vitro . We hypothesize that decreased levels of cytoplasmic HuR may contribute to decreased PlGF expression in hypoxic and preeclamptic trophoblast.
Methods: Western blots were used to determine relative effects of in vitro hypoxia on HuR protein expression and subcellular localization in trophoblast. Immunohistochemistry was used to compare HuR expression patterns in trophoblast of preeclamptic and normal placentae.
Results: Cytoplasmic expression of HuR was decreased 1.4 fold in the cytoplasm and 1.2 fold in the nucleus of JEG3 cells. A shift in HuR was more apparent in primary trophoblast with a greater than 2-fold decrease in the cytoplasm and a 1.4 fold decrease in the nucleus following 24 hr of hypoxia. Immunohistochemical analyses detected HuR expression in near term trophoblast in situ . However, this technical approach did not detect a significant change in HuR expression between normal and preeclamptic trophoblast.
Conclusions: HuR expression is decreased in hypoxic trophoblast, at least in vitro , which may provide a causal link to decreased PlGF mRNA expression. Down regulation of trophoblast PlGF expression is thought to contribute to the pathophysiology associated with preeclampsia including the relative lack of perfusion of the placenta and systemic renal effects. 相似文献
Methods: Western blots were used to determine relative effects of in vitro hypoxia on HuR protein expression and subcellular localization in trophoblast. Immunohistochemistry was used to compare HuR expression patterns in trophoblast of preeclamptic and normal placentae.
Results: Cytoplasmic expression of HuR was decreased 1.4 fold in the cytoplasm and 1.2 fold in the nucleus of JEG3 cells. A shift in HuR was more apparent in primary trophoblast with a greater than 2-fold decrease in the cytoplasm and a 1.4 fold decrease in the nucleus following 24 hr of hypoxia. Immunohistochemical analyses detected HuR expression in near term trophoblast in situ . However, this technical approach did not detect a significant change in HuR expression between normal and preeclamptic trophoblast.
Conclusions: HuR expression is decreased in hypoxic trophoblast, at least in vitro , which may provide a causal link to decreased PlGF mRNA expression. Down regulation of trophoblast PlGF expression is thought to contribute to the pathophysiology associated with preeclampsia including the relative lack of perfusion of the placenta and systemic renal effects. 相似文献
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Bedilu R Nummy KA Cooper A Wevers R Smeitink J Kleijer WJ Friderici KH 《Molecular genetics and metabolism》2002,77(4):282-290
Beta-mannosidosis is an autosomal recessive lysosomal storage disease resulting from a deficiency of the lysosomal enzyme beta-mannosidase. The clinical manifestations of this disease in reported human cases are very heterogeneous ranging from relatively mild to moderately severe. This is in contrast with the severe prenatal onset seen in ruminant beta-mannosidosis. In humans, mental retardation, hearing loss, frequent infections, and behavioral problems are relatively common. Dysmorphology and skeletal involvement such as those seen in ruminants are unusual. The purpose of this study is to determine the range of clinical expression in human beta-mannosidosis resulting from null mutations. We determined that the beta-mannosidase gene consists of 17 exons. Intron-based PCR primers were designed and used to amplify each of the exons in genomic DNA isolated from patient fibroblasts. We identified two patients with null mutations. Results of the analysis showed that one patient was heterozygous for nonsense mutations G334T (E83X) in exon 2 and C1363T (Q426X) in exon 10, resulting in truncation of the deduced peptide sequence from 879 to 82 and 425 amino acids, respectively. The second patient was homozygous for a deletion mutation in exon 11 (1541delAT). This deletion causes a reading frame shift and 26 out of frame amino acids before a stop codon occurs in exon 12, resulting in truncation of the deduced peptide sequence from 879 to 510 amino acids. Because disease presentation in these patients with null mutations is very variable, ranging from mild to severe, we conclude that beta-mannosidosis in humans may indeed be milder than typical of other lysosomal storage disorders. 相似文献
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目的:探讨物理课程在高等医药类专业教育中的作用与地位。方法:对全国部分城市不同类别医院从业医务工作者进行调查,综合国际医学教育标准和我国现实医学教育以及医疗服务行业状况进行分析。结果:探讨了我国高等医药类专业教育中物理课程的设置及目标与定位问题,给出了明确的课程定位与设置标准。结论:现代医学高等教育不应忽视或淡化物理课程在医学人才培养中素质教育和专业水平提高的积极作用与基础地位,在有限的学时空间内合理安排基础性内容和与专业素质培养相关的应用内容。 相似文献
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目的;探讨手术治疗胸椎结核的更好方法。方法;自1990年以来,对21例胸椎结核导致椎柱不稳的患者,应用病灶清除,哈氏棒内固定,椎间及椎板植骨的手术方法。本组平均33.2岁。胸7椎体6例,胸8椎体8例,胸10椎体7例,椎体压缩〈1/2椎体高度13例,〉1/2椎体高度8例,并不全瘫14例。手术中先行病灶清除,然后哈氏棒内固一,撑开后再次清除病灶,取肋骨和髂骨行椎间及椎板上植骨。术后化疗12~15月。结 相似文献