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11.
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
12.
Marjolein P de Vries Lisette van den Bemt Karen Aretz Bart PA Thoonen Jean WM Muris Arnold DM Kester Sonja Cloosterman CP Onno van Schayck 《The British journal of general practice》2007,57(536):184-190
BACKGROUND: The efficacy of bed covers that are impermeable to house dust mites has been disputed. AIM: The aim of the present study was to investigate whether the combination of 'house dust mite impermeable' covers and a self-management plan, based on peak flow values and symptoms, leads to reduced use of inhaled corticosteroids (ICS) than self-management alone. DESIGN OF STUDY: Prospective, randomised, double blind, placebo-controlled trial. SETTING: Primary care in a south-eastern region of the Netherlands. METHOD: Asthma patients aged between 16 and 60 years with a house dust mite allergy requiring ICS were randomised to intervention and placebo groups. They were trained to use a self-management plan based on peak flow and symptoms. After a 3-month training period, the intervention commenced using house dust mite impermeable and placebo bed covers. The follow-up period was 2 years. Primary outcome was the use of ICS; secondary outcomes were peak expiratory flow parameters, asthma control, and symptoms. RESULTS: One hundred and twenty-six patients started the intervention with house dust mite impermeable or placebo bed covers. After 1 and 2 years, significant differences in allergen exposure were found between the intervention and control groups (P<0.001). No significant difference between the intervention and control groups was found in the dose of ICS (P = 0.08), morning peak flow (P = 0.52), peak flow variability (P = 0.36), dyspnoea (P = 0.46), wheezing (P = 0.77), or coughing (P = 0.41). There was no difference in asthma control between the intervention and control groups. CONCLUSION: House dust mite impermeable bed covers combined with self-management do not lead to reduced use of ICS compared with self-management alone. 相似文献
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Kochakian Charles D.; Raut V. S.; Kinson Gordon 《The American journal of physiology》1961,200(2):348-350
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The effectiveness of a treatment protocol for male lower urinary tract symptoms in general practice: a practical randomised controlled trial 下载免费PDF全文
Roelf JC Norg Kees van de Beek Piet JM Portegijs CP Onno van Schayck J Andr Knottnerus 《The British journal of general practice》2006,56(533):938-944
BACKGROUND: Randomised controlled trials have shown the efficacy of several treatment modalities for lower urinary tract symptoms (LUTS) in selected populations. The effectiveness in daily practice has hardly been investigated, especially in primary care and is dependent on choices between all possible treatment options and best investigated in a comprehensive study, including all treatment modalities (watchful waiting, alpha-blockers, 5-alpha-reductase inhibitors, and surgery). AIM: Assessment of the effectiveness of a comprehensive treatment protocol for LUTS in primary care. DESIGN OF STUDY: Randomised controlled trial. SETTING: Fourteen general practices in the Netherlands. METHOD: Intervention: treatment protocol based on a formalised expert opinion. Control condition: usual care. Study population: 208 subjects with moderate to severe LUTS (IPSS > or =8, median = 13). OUTCOME MEASURES: symptom severity (IPSS [International Prostate Symptom Score]), bother score (Dan-PSS [Danish Prostate Symptom Score]), and maximum urinary flow (Q(max)); incidence of acute urinary retention and urinary tract infections. RESULTS: In the intervention group markedly more subjects used an alpha-blocker at end of follow-up than in the usual care group (24% versus 6%). No significant differences were found between intervention and control group in IPSS, Q(max) or Dan-PSS. CONCLUSION: alpha-blockers and watchful waiting are the most frequent treatment modalities for LUTS in primary care. Our study showed no evidence that a protocol using well-defined indications for all possible treatment modalities based on a formalised expert opinion procedure has added value. Based on our results, we cannot recommend a broadening of the indication for alpha-blockers, which, however, seems to be the current trend. 相似文献
17.
Measurement of albumin and low molecular weight proteins in the urine of newborn infants using a cotton wool ball collection method 总被引:2,自引:0,他引:2
Objective : The aim of this study was to investigate the inter-relationship between urinary excretion of alpha-1-microglobulin (AIM), retinol-binding protein (RBP) and albumin in term and premature neonates, with urine collected into cotton wool balls and extracted by a novel method. Subjects and methods : Sixty-four infants were studied on the first day of life; 26 had been born at term (37–42 weeks gestation) and 38 prematurely (24–28 weeks n = 16, 29–36 weeks n = 22). Urine collected into cotton wool balls was analysed following a new detergent extraction method, which resulted in a recovery rate of 94–107% for albumin, AIM, RBP and creatinine. Results : Urinary protein excretion, expressed as a ratio to urinary creatinine, decreased significantly with increasing gestational age (24–28 weeks, 29–36 weeks, 37–42 weeks: albuminxreatinine ratio mg/mmol mean 96.9, 31.7, 19.3; AIM: creatinine ratio mg/mmol mean 99.3, 37.0, 7.8; RBP: creatinine ratio mg/mmol mean 16.2, 3.8, and <0.01, below the limit of detection, respectively). When results were corrected for birthweight, this gestation-associated effect was still present for A1M and RBP, but not for albumin. In premature infants there was a significant positive correlation between AIM: creatinine ratio and RBP: creatinine ratio ( r = 0.85), and also between albumin and both AIM and RBP ( r = 0.82 and 0.77). Conclusion : Increased excretion of AIM, RBP and albumin at earlier gestational ages is probably due to proximal tubular immaturity, although tubular damage and also glomerular dysfunction cannot be excluded as possible explanations. 相似文献
18.
CP Panayiotopoulos 《Archives of disease in childhood》1998,78(6):575-6; discussion 576-7
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Vandhana Sundaram Sujithra Haridas Meenakshi Dhar CP Harikrishnan 《Indian journal of ophthalmology》2022,70(2):453
Purpose:To compare the retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), and optic nerve head (ONH) morphological parameters between obstructive sleep apnea (OSA) patients and age-matched controls using spectral domain optical coherence tomography (SD-OCT).Methods:This case control study was conducted in a multi-specialty tertiary care hospital from 2014 to 2016. Patients diagnosed to have OSA by overnight polysomnography were included in the study. Fifty eyes of 25 OSA patients with clinically normal optic disc were compared with 50 eyes of age-matched controls. The study population underwent detailed ophthalmological evaluation including SD-OCT.Results:There was significant thinning of the superior, inferior, and average RNFL in the OSA group when compared to controls. GCL analysis also showed a significant thinning of the six sectors as well as average and minimum ganglion cell layer + inner plexiform layer in OSA patients. The optic nerve head rim area was significantly decreased in OSA patients when compared to controls.Conclusion:OSA patients even with clinically normal optic disc showed significant decrease in the RNFL thickness, GCL thickness, and rim area when compared to age-matched controls. Hence, these patients constitute a high-risk population who need to be regularly screened and followed up for ocular co-morbidities. 相似文献