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We have previously shown that the estrogen responsiveness of the human lactoferrin gene in a transient transfection system is mediated through an imperfect estrogen response element (ERE) and a steroidogenic factor 1 binding element (SFRE) 26 bp upstream from ERE. Reporter constructs containing SFRE and ERE respond to estrogen stimulation in a dose-dependent manner, whereas mutations at either one of the response elements severely impaired the estrogen responsiveness. In this study, we demonstrated that estrogen receptor (ERalpha) binds to the human lactoferrin gene ERE and forms two complexes in an electrophoresis mobility shift assay (EMSA). These complexes could be supershifted by an antibody to ERalpha. We also showed that in normal cycling women, lactoferrin gene expression in the endometrium increases during the proliferative phase and diminishes during the luteal phase. This in-vivo study thus supported the finding from transient transfection experiments that the human lactoferrin gene expression is elevated in an environment with a high level of estrogen. The estrogen effect on lactoferrin gene expression in the rhesus monkey endometrium was studied by Western blotting and immunohistochemistry. The immunohistochemistry results showed that immunoreactive lactoferrin protein was not detectable in the untreated ovariectomized monkey endometrium, was elevated by estrogen treatment, and was suppressed by sequential, combined estrogen plus progesterone treatment. In conclusion, this study has shown that lactoferrin gene expression is responsive to estrogen in primate endometrium.  相似文献   
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Agouti related protein (AgRP) is a recently discovered melanocortin receptors (MCR) antagonist implicated in the control of feeding behaviour. Expression of AgRP has been shown to be localized by in situ hybridization to the arcuate nucleus and median eminence of the brain, where it acts as an antagonist to the MC3 and MC4 receptors, while in the periphery the only significant expression was located in the adrenal medulla. As AgRP is only a weak antagonist of the MC2 and MC5 receptors, which are expressed principally by adipocytes and in the adrenal cortex, the question arizes as to the function of peripheral AgRP. In this study, we investigated the expression of AgRP in the rat adrenal and suggest that it is expressed in the adrenal cortex and not as previously described in the medulla. We also show that AgRP mRNA expression is upregulated in the adrenal during fasting and in the contralateral gland following unilateral adrenalectomy but not during chronic stress. These results indicate an as yet undefined role for AgRP in the periphery and are supportive of the suggestion that a further melanocortin receptor exists.  相似文献   
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A patient with a lifelong bleeding disorder was diagnosed as having Type II von Willebrand disease. The larger multimers of von Willebrand factor were absent from her plasma but present in platelets. A high- resolution electrophoretic technique was used to study the complex structure of individual von Willebrand factor multimers. In normal plasma, each multimer could be resolved into five bands: a more intense central one and four less intense, two moving faster and two slower than the central band. In normal platelets, each multimer could also be resolved into five bands. The central one had a mobility similar to that in plasma, whereas the four satellite bands had a mobility that differed from that of the corresponding plasma bands. In the patient, platelet von Willebrand factor antigen content and ristocetin cofactor activity were normal, and von Willebrand factor showed the same structure of individual multimers as seen in normal platelets. On the other hand, plasma von Willebrand factor antigen and ristocetin cofactor activity were decreased, and the structure of individual von Willebrand factor multimers was different from that of normal plasma and similar to that seen in normal and patient's platelets. After infusion of 1-deamino-8-D-arginine vasopressin, the largest von Willebrand factor multimers, as well as new satellite bands with a mobility similar to those in normal plasma, appeared in the patient plasma, and the levels of von Willebrand factor antigen and ristocetin cofactor activity became normal. Yet no relevant change in the prolonged bleeding time was observed. This new variant of von Willebrand disease, therefore, is characterized by the presence of a dysfunctional von Willebrand factor molecule that exhibits unique structural abnormalities in plasma but appears to be normal in platelets. The designation of Type IIF is proposed for this type of von Willebrand disease in accordance with the terminology that has been previously used.  相似文献   
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The voltage-gated sodium channel NaV1.8 (SNS, PN3) is thought to be a molecular correlate of the dorsal root ganglion (DRG) tetrodotoxin resistant (TTX-R) Na+ current. TTX-R/NaV1.8 is an attractive therapeutic drug target for inflammatory and neuropathic pain on the basis of its specific distribution in sensory neurones and its modulation by inflammatory mediators. However, detailed analysis of recombinant NaV1.8 has been hampered by difficulties in stably expressing the functional protein in mammalian cells. Here, we show stable expression and functional analysis of rat NaV1.8 (rNaV1.8) in the rat DRG/mouse N18Tg2 neuroblastoma hybridoma cell line ND7-23. Rat NaV1.8 Na+ currents were recorded (789 +/- 89 pA, n=62, over 20-cell passages) that qualitatively resembled DRG TTX-R in terms of gating kinetics and voltage-dependence of activation and inactivation. The local anaesthetic drug tetracaine produced tonic inhibition of rNaV1.8 (mean IC50 value 12.5 microM) and in repeated gating paradigms (2-10 Hz) also showed frequency-dependent block. There was a correlation between the ability of several analogues of the anticonvulsant/analgesic compound lamotrigine to inhibit TTX-R and rNaV1.8 (r=0.72, P<0.001). RT-PCR analysis of wild type ND7-23 cells revealed endogenous expression of the beta1 and beta3 accessory Na+ channel subunits-the possibility that the presence of these subunits assists and stabilises expression of rNaV1.8 is discussed. We conclude that the neuroblastoma ND7-23 cell line is a suitable heterologous expression system for rNaV1.8 Na+ channels in that it allows stable expression of a channel with biophysical properties that closely resemble the native TTX-R currents in DRG neurones. This reagent will prove useful in the search for pharmacological inhibitors of rNaV1.8 as novel analgesics.  相似文献   
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目的:严重的多节段脊髓型颈椎病单纯前路或后路手术都有其局限性。观察一期前后路联合手术并自体髂骨植骨及带锁钢板内固定材料置入在治疗多节段脊髓型颈椎病中的应用价值。方法:选择2004-11/2006-12本院12例多节段脊髓型颈椎病患者,均采用一期前后路减压、自体髂骨植骨融合、带锁钢板内固定联合手术。其中男9例,女性3例,年龄49~75岁;3节段受累9例,4节段受累3例(突出节段分布:C3~66例,C4~73例,C3~73例)。全部病例进行临床随访,患者均对本试验知情同意。采用mJOA评分标准对患者神经功能改善情况进行评定;术前颈椎侧位片测量,以D值(C4椎体后下缘到齿突后缘与C7椎体后下缘连线的垂直距离)评价颈椎(C2~7)弧度;根据颈椎伸屈动态侧位片C2和C7椎体后缘切线相交所成的夹角之和评价颈椎(C2~7)活动范围。主要以电话随访和问卷填写的方式,分别从神经功能改善情况、颈椎弧度、活动范围及术后并发症等进行随访观察。结果:①12例患者全部得到随访,术后随访时间6~28个月,平均(16±6)个月。②所有植骨均获得骨性愈合;疗效结果中优4例(33.3%);良6例(50%);无效2例(16.7%);颈椎D值术前(3.9±1.4)mm,术后即刻(8.5±1.7)mm,随访时(8.1±2.5)mm。术前与术后差异有显著性(P<0.01),术后与随访时差异无显著性(P=0.251);颈椎活动范围术前(36.3±4.0)°,随访时(10.6±2.7)°,与术前相比差异具有显著性(P<0.01)。③术后C5神经根麻痹1例,为感觉及运动混合型,8个月随访时,感觉功能恢复,肩关节外展肌力从术后Ⅱ级恢复至Ⅳ级;1例术后6个月出现"S"畸形而再次压迫脊髓,神经功能改善停滞,目前处于随访中。结论:一期前后路手术并自体髂骨植骨及带锁钢板内固定材料置入减压充分、彻底,而且前路手术能重建颈椎稳定性,恢复颈椎生理前凸和椎间高度,并且后路减压术又能预防相邻颈椎退变引起的脊髓继发的压迫。  相似文献   
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