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LR Green, Y Kawagoe, DJ Hill, BS Richardson and VK Han

Intermittent umbilical cord compression with resultant fetal hypoxia can have a negative impact on fetal growth and development. Insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are the most important regulators of fetal growth. In preterm (107-108 days of gestation) and near-term (128-131 days of gestation) ovine fetuses, we have determined the effect of intermittent umbilical cord occlusion (UCO) over a period of 4 days on the profile and expression of IGFs and IGFBPs. In experimental group animals (preterm n=7; near term n=7) UCOs were carried out by complete inflation of an occluder cuff (duration 90 s) every 30 min for 3-5 h each day, while control fetuses (preterm n=7; near term n=7) received no UCOs. Ewes were euthanized at the end of day 4, and fetal heart, lung, kidney, liver, skeletal muscle and placenta were collected. During UCOs, PO(2! ) fell (by approximately 13 mmHg), pH fell (by approximately 0.05) and PCO(2) increased (by approximately 7 mmHg), and changed to a similar extent in both preterm and near-term groups. In both preterm and near-term groups, there was no difference in fetal body or organ weight between UCO and control fetuses. No significant changes were observed in plasma IGF-I and -II concentrations or IGFBP-1, -2, -3 or -4 levels throughout the 4-day study at either gestational age. In the preterm group UCO fetuses, IGF-II mRNA (1.2-6.0 kb) levels were lower in fetal lung (33%, P<0.05), heart (54%, P<0.01) and skeletal muscle (29%, P<0.05), but there were no differences in IGF-I mRNA levels (7.3 kb); IGFBP-2 mRNA (1.5 kb) levels were lower in the right lobe of the liver (42%, P<0.05) and kidney (22%, P<0.01), but hig! her in the heart (72%, P<0.01), while IGFBP-4 (2.4 kb) levels were lower in skeletal muscle (21%, P<0.01). In the near-term group UCO fetuses, IGFBP-2 mRNA levels were greater in the placenta (39%, P<0.05). Thus, intermittent UCO as studied has a greater effect on the expression of genes encoding certain peptides of the fetal IGF system in selected tissues in preterm fetuses than that in near-term fetuses. Altered IGFBP-2 mRNA levels with reduced IGF-II mRNA levels in selected tissues may mediate changes in growth and/or differentiation that might become apparent if the length of the UCO study were extended.

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Rui Song, Xiang-Qun Hu and Lubo Zhang

provide clues to understand glucocorticoids regulating DNA methylation via GR in heart development and disease. Perinatal hypoxia and glucocorticoid exposure cause fetal programming during fetal development, leading to an increased risk of adult disease

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Stephen Mandang, Ursula Manuelpillai and Euan M Wallace

output remain unclear. On the basis of histological ( Brosens & Renaer 1972 ) and, more recently, molecular ( Soleymanlou et al. 2005 ) evidence of placental hypoxia in preeclampsia and on the in vivo observations in sheep that both acute

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A L Pierce, M Shimizu, L Felli, P Swanson and W W Dickhoff

IGFBP-1 mRNA levels are directly increased by low amino acid levels ( Thissen et al. 1994 ) and by hypoxia ( Popovici et al. 2001 , Scharf et al. 2005 ). Both the regulation of IGFBP-1 by metabolic status and stress and its function as an

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Angélica Morales, Sumiko Morimoto, Lorenza Díaz, Guillermo Robles and Vicente Díaz-Sánchez

). EG-VEGF regulation is poorly understood; nevertheless, recent studies have shown that hypoxia induces EG-VEGF expression, suggesting a role of this factor in tumorigenesis. In addition, EG-VEGF has been associated with certain EG cancers such as

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Amy Hughes, Darling Rojas-Canales, Chris Drogemuller, Nicolas H Voelcker, Shane T Grey and P T H Coates

, O'Connell et al . 2013 ). Islet allotransplantation into a recipient with T1D exposes the transplanted islets to a number of apoptotic stresses, including the instant blood-mediated inflammatory reaction (IBMIR), hypoxia, inflammation, hyperglycemia

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Chao Li, Bin Yang, Zhihao Xu, Eric Boivin, Mazzen Black, Wenlong Huang, Baoyou Xu, Ping Wu, Bo Zhang, Xian Li, Kunsong Chen, Yulian Wu and Gina R Rayat

, total AKT, Lamin B1 or β-actin and the values were expressed as normalized data relative to the control. Exposure of islets to H 2 O 2 and hypoxia To determine the effect of C3G on islet injury induced by ROS, 1000 IEQs were cultured with or

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Weixia Han, Chen Wang, Zhifen Yang, Lin Mu, Ming Wu, Nan Chen, Chunyang Du, Huijun Duan and Yonghong Shi

). However, effects of SRT1720 on DN remain unknown. Chronic hypoxia has been implicated in the development and progression of DN ( Singh et al. 2008 ). Hypoxia inducible factor 1 alpha (HIF1A) is a key transcriptional regulator of cellular adaptation to

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David E Henley, Fiona Buchanan, Rosemary Gibson, Jennie A Douthwaite, Susan A Wood, Wolfram W Woltersdorf, James R Catterall and Stafford L Lightman

subsequent hypoxia and autonomic arousal during sleep, resulting in fragmented sleep with daytime somnolence ( Buckley & Schatzberg 2005 ). Morbidity and mortality from OSA are primarily due to cardiovascular disease ( Peter et al . 1995 , Collop 2007

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Alpha Dian-Yu Lin, Anita Mannikarottu, Barry A Kogan, Catherine Whitbeck, Paul Chichester, Robert E Leggett and Robert M Levin

hypertrophy. In addition, we investigated the expression of two highly potent angiogenic markers, vascular endothelial growth factor (VEGF) and hypoxia inducible factor (HIF-1α) in the hypertrophied bladder. Materials and Methods