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1.
Previously, we have demonstrated that chronic-alcohol exposure alters insulin-like growth factor 1 (IGF1) signaling in adult rat heart cells. This report examines the effects of alcohol in vitro on the expression of protein kinase C (PKC) alpha, delta, and epsilon using the embryonic heart cell line, H9c2, and how this may be linked to changes in IGF1 signal transduction. Western blot analyses of H9c2 protein preparations demonstrate that there are significant increases in the total protein levels of PKC delta and epsilon after 4 days exposure to alcohol, and similar increases were found after 2 and 6 days exposure. In addition, there was a significant increase in PKC delta and epsilon in the membranal fractions and a decrease in the cytosolic fractions. No change was found in the expression or activity levels for PKC alpha. Chronic-alcohol exposure (100 mM, 4 days) increased the basal tyrosine kinase activity of the IGF1 receptor (IGF1R), and altered its rate of activation. Chronic-alcohol exposure also reduced the rate of Erk1/Erk2 activation by IGF1. Chronic alcohol blocked the proliferative effects of IGF1 on cell growth and reduced cell viability both in the presence and absence of IGF1, and this alcohol-induced reduction in cell viability was blocked using siRNA to inhibit PKC delta. In addition, a reduction in the amount of myosin light chain 2 was found in the alcohol-exposed cells. In conclusion, chronic alcohol alters PKC delta and epsilon expression and activity, and suppresses the IGF1 signaling pathway in embryonic heart cell culture. Blockage of PKC delta expression using siRNA inhibits the suppressive effects of alcohol on cell viability. 相似文献
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Background Germinal matrix and intraventricular hemorrhage (GMH/IVH) is a known complication occurring in the first week of life in preterm neonates. However, the precise time of its occurrence and the ideal time to perform diagnostic imaging studies remain controversial. The purpose of this paper is to address these two issues in our patient population to allocate our resources to those at highest risk.Materials and methods This study included 282 premature newborns (under 37 weeks of gestation) that were admitted to our neonate ICU in a year’s time and screened for GMH/IVH. They were grouped in four categories according to their weight at birth, and according to their gestational age. All patients had a daily cranial ultrasound during the first week. It was then repeated once in the second week and once in the third.Results We found that the incidence of GMH/IVH among preterm neonates was 44.68%. It was inversely related to the weight and the age of the newborn. The onset of bleeding coordinated with the occurrence of hypoxia and respiratory distress requiring mechanical ventilation. The majorities occurred in the first 7 days of life; they were mostly grade I and II according to the Papule classification and silent for the most part. Complications were present in 41% of the survivors. 相似文献
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Kadri Oumaima Karmous Inès Kharbech Oussama Arfaoui Hiba Chaoui Abdelilah 《Bulletin of environmental contamination and toxicology》2022,108(3):585-593
Bulletin of Environmental Contamination and Toxicology - The application of Cu and CuO nanofertilizers in horticulture has been a promising strategy to promote plants’ growth. In our study,... 相似文献
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Proton magnetic resonance spectroscopy improves outcome prediction in perinatal CNS insults. 总被引:4,自引:0,他引:4
Munaf Kadri Stanford Shu Barbara Holshouser Douglas Deming Andrew Hopper Ricardo Peverini Stephen Ashwal 《Journal of perinatology》2003,23(3):181-185
OBJECTIVE: Prediction of neurologic outcome is difficult in neonates with acute nervous system injury. Previous studies using proton magnetic resonance spectroscopy ((1)H-MRS) have been used to predict short-term neurologic outcome in neonates with a variety of neurologic insults. We were interested in determining the effectiveness of combining clinical evaluation and spectroscopy obtained at the time of injury in predicting neurologic outcome at 24 months. STUDY DESIGN: We studied 33 neonates with acute central nervous system injury, 5.8+/-3.7 days of injury, owing to hypoxic-ischemic encephalopathy. Neonates were assessed using clinical variables (initial arterial pH, initial blood glucose, Sarnat score, electroencephalography) and spectroscopy (NAA/Cho, NAA/Cre, Cho/Cre, and lactate). Neonates were divided into two outcome groups: good/moderate and poor. Differences between the groups were assessed using chi(2) and t-test analyses. We analyzed the best predictors of outcome using discriminant analysis and calculated sensitivity, specificity, positive, and negative predictive values for each variable independently and in combination. RESULTS: There were significant differences between the good/moderate and poor outcome for the Sarnat score, EEG, lactate, and NAA/Cho. Spectroscopy combined with clinical variables improved sensitivity, but not specificity for predicting outcome. The presence of lactate had the best individual predictive value. Combination of the clinical with the MRS variables had the highest predictive value. CONCLUSION: Proton magnetic resonance spectroscopy done early after injury improves the ability to predict neurologic outcome at 24 months of age. 相似文献
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Kadri Altundag Ozden Altundag Paolo Morandi Mehmet Gunduz 《Journal of clinical oncology》2005,23(10):2435-6; author reply 2436
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Journal of Neuro-Oncology - 相似文献
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Ila Datar Xiaoliang Qiu Hong Zhi Ma Miranda Yeung Shweta Aras Ivana de la Serna Fahd Al-Mulla Jean Paul Thiery Robert Trumbly Xuan Fan Hongjuan Cui Kam C. Yeung 《Oncotarget》2015,6(36):39050-39061
Accumulating evidence suggests that presence of macrophages in the tumor microenvironment add to the invasive and tumor-promoting hallmarks of cancer cells by secreting angiogenic and growth factors. RKIP is a known metastasis suppressor and interferes with several steps of metastasis. However, the mechanistic underpinnings of its function as a broad metastasis suppressor remain poorly understood. Here, we establish a novel pathway for RKIP regulation of metastasis inhibition through the negative regulation of RANTES/CCL5 thereby limiting tumor macrophage infiltration and inhibition of angiogenesis. Using a combination of loss- and gain-of-function approaches, we show that RKIP hinders breast cancer cell invasion by inhibiting expression of the CC chemokine CCL5 in vitro. We also show that the expression levels of RKIP and CCL5 are inversely correlated among clinical human breast cancer samples. Using a mouse allograft breast cancer transplantation model, we highlight that ectopic expression of RKIP significantly decreases tumor vasculature, macrophage infiltration and lung metastases. Mechanistically, we demonstrate that the inhibition of the CCL5 expression is the cause of the observed effects resulting from RKIP expression. Taken together, our results underscore the significance of RKIP as important negative regulator of tumor microenvironment. 相似文献