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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   
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A monoclonal antibody (mAbIIa138) raised against the second-loop undecapeptide (residues [21-31]) of human transforming growth factor alpha, known to be involved in binding to its cell receptor, was found to define a hexapeptide epitope (RFLVQE, residues [22-27]). In enzyme-linked immunosorbent assay testing mAbIIa138 did not react with either native or reduced human transforming growth factor alpha, indicating that conformational restraints in this protein interfered with the antigenicity of the cognate sequence. Despite its failure to react with human transforming growth factor alpha, this monoclonal antibody proved very interesting when used to immunostain mammalian cells. mAbIIa138 was found to bind with great specificity to the centrosomes of late-interphase and mitotic cells. The staining of the centrosomes was most intense when the centrosomes were active in organizing the mitotic spindle and faded during telophase as the spindle was disaggregated. The epitope that mAbIIa138 recognizes is thus in a centrosomal protein, denoted CSP alpha, involved in some aspect of mitotic spindle organization or function. Analysis of the antigenic stringency of the epitope, using an amino acid replacement set, showed that 25 individual single amino acid replacements were possible without significant loss of antigenicity. Data bank searches for proteins of possible relevance were unsuccessful, so CSP alpha is an as yet unsequenced protein, specific to the centrosome.  相似文献   
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KA Daly  RE Selvius  B Lindgren 《Pediatrics》1997,100(6):931-936
OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for 相似文献   
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John Kerr and apoptosis   总被引:1,自引:0,他引:1  
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目的:评价前后路短节段固定融合治疗腰椎纵向劈裂骨折的临床效果和安全性。方法:回顾性分析中南 大学湘雅二医院脊柱外科2005年3月至2013年5月采用的前后路短节段固定融合治疗的13例腰椎纵向劈裂骨折患者临床 资料,对所有患者的矫正情况进行随访,采用疼痛视觉模拟量表(visual analogue scale,VAS)评分、Oswestry功能障碍指 数(Oswestry disability index,ODI)对腰椎功能进行评估。结果:随访时间为24~60个月,平均42个月;手术时间185~300 min,平均248 min;术中失血量为600~1 500 mL,平均950 mL。所有患者术后均获得功能及自我形象的改善,在Cobb 角评估方面,术后2 d,12个月和末次随访测量Cobb角较手术前均有明显改善,差异均有统计学意义(P<0.05);VAS评 分和ODI评估术后2 d,12个月和末次随访测量结果较之术前均有改善, 差异均有统计学意义(P<0.05)。术后12个月与 末次随访的评估结果相比,差异无统计学意义(P>0.05)。根据美国脊髓损伤协会(ASIA)分级标准,在末次随访时,术 前8例D级患者中6例恢复至E级,其中3例未见进一步恢复;术前2例C级中1例恢复至D级,1例恢复至E级。所有病例 骨折均获愈合,愈合时间为3~6个月,平均4.5个月;术中3例有硬膜撕裂,术中给予修补;无神经血管损伤并发症病 例。结论:短节段伤椎置钉和旋棒复位是腰椎纵向劈裂不稳定骨折较好的手术选择。  相似文献   
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马骁  卡索  刘成  李丹  刘守应  王永成 《中国骨伤》2012,25(4):338-340
目的:探讨前后路联合手术治疗髋臼双柱骨折的效果并分析影响疗效的相关因素。方法:2007年8月至2009年7月收治髋臼双柱骨折患者19例,男13例,女6例;年龄27~52岁,平均39.6岁。高位双柱骨折11例,低位双柱骨折8例,双柱骨折累及骶髂关节1例。受伤至手术时间4~11 d,平均5.8 d。患者均采用前后联合入路手术,重建钢板和螺钉内固定。结果:除1例死亡外本组全部获随访,随访时间12~18个月,平均13.6个月。关节功能根据Harris评分标准,术后功能优9例,良7例,可2例。结论:经前后路联合切开复位内固定治疗髋臼双柱骨折疗效满意。  相似文献   
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