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101.
Integrins participate in the pathogenesis and progression of tumors at many stages during the metastatic cascade. However, current evidence for the role of integrins in breast cancer progression is contradictory and seems to be dependent on tumor stage, differentiation status, and microenvironmental influences. While some studies suggest that loss of α2β1 enhances cancer metastasis, other studies suggest that this integrin is pro-tumorigenic. However, few studies have looked at α2β1 in the context of bone metastasis. In this study, we aimed to understand the role of α2β1 integrin in breast cancer metastasis to bone. To address this, we utilized in vivo models of breast cancer metastasis to bone using MDA-MB-231 cells transfected with an α2 expression plasmid (MDA-OEα2). MDA cells overexpressing the α2 integrin subunit had increased primary tumor growth and dissemination to bone but had no change in tumor establishment and bone destruction. Further in vitro analysis revealed that tumors in the bone have decreased α2β1 expression and increased osteolytic signaling compared to primary tumors. Taken together, these data suggest an inverse correlation between α2β1 expression and bone-metastatic potential. Inhibiting α2β1 expression may be beneficial to limit the expansion of primary tumors but could be harmful once tumors have established in bone.  相似文献   
102.
Maternal smoking is a risk factor of preterm prelabor rupture of the fetal membranes (pPROM), which is responsible for 30% of preterm births worldwide. Cigarettes induce oxidative stress and inflammation, mechanisms both implicated in fetal membranes (FM) weakening. We hypothesized that the receptor for advanced glycation end-products (RAGE) and its ligands can result in cigarette-dependent inflammation. FM explants and amniotic epithelial cells (AECs) were treated with cigarette smoke condensate (CSC), combined or not with RAGE antagonist peptide (RAP), an inhibitor of RAGE. Cell suffering was evaluated by measuring lactate dehydrogenase (LDH) medium-release. Extracellular HMGB1 (a RAGE ligand) release by amnion and choriodecidua explants were checked by western blot. NF-κB pathway induction was determined by a luciferase gene reporter assay, and inflammation was evaluated by cytokine RT-qPCR and protein quantification. Gelatinase activity was assessed using a specific assay. CSC induced cell suffering and HMGB1 secretion only in the amnion, which is directly associated with a RAGE-dependent response. CSC also affected AECs by inducing inflammation (cytokine release and NFκB activation) and gelatinase activity through RAGE engagement, which was linked to an increase in extracellular matrix degradation. This RAGE dependent CSC-induced inflammation associated with an increase of gelatinase activity could explain a pathological FM weakening directly linked to pPROM.  相似文献   
103.
Fetal development can be influenced by maternal environment in the peri-conceptional period. This study investigated the effect of maternal feed intake and psychological stress within the first 6 days after conception on embryo development and fetal growth. Superovulated ewes (n=40) were artificially inseminated with semen from one ram. Ewes were then divided into four groups (n=10): group 1 (control) was fed at maintenance level, group 2 (high) at 2x maintenance, and group 3 (low) at 0.5x maintenance on days 2-6 after conception. Group 4 (stress) was fed at maintenance level and then an intense physical and psychological stress challenge was applied for 1 h only on days 2 and 3 after conception. Embryos were recovered at day 6. A total of 113 transferable grade embryos were transferred singly into synchronized untreated recipients, while the remaining embryos (n=165) were fixed and stained for cell counts. Post-conception maternal stress or feed intake did not alter the cell count or grade of day 6 embryos. Fetuses from the stress group had longer crown-rump lengths at day 30 and longer femur length at day 58. Fetuses from the stressed and high feed groups had greater abdominal circumferences at day 85. Subsequent birth weights were not significantly different. Ewes carrying lambs from the stress treatment had shorter gestation lengths. These results show that short-term perturbations of the post-conception maternal environment have measurable effects on fetal development and gestation length.  相似文献   
104.
在上期的报告中,我们谈到用户越来越多地集中资源.将文件应用程序和跨媒体互动(CMI)组合在一起。在本期的评论中,我们要探讨企业对跨媒体互动如此感兴趣的原因.跨媒体互动的兴起,以及跨媒体互动正在对印刷行业产生的积极影响。  相似文献   
105.
Quitting smoking benefits older individuals, yet few recent studies have described older smokers. The goal of this paper was to test a series of hypotheses about differences between smokers aged 50 years or older (50+) and those younger than age 50 (<50) presenting to the same treatment facility during 2002-2004 for participation in two randomized clinical trials: one exclusively for smokers aged 50+, and a second open to smokers aged 18 or older. As predicted, smokers aged 50+ were more tobacco dependent, had better psychological functioning, and had poorer physical functioning than those aged <50. Contrary to predictions, we found no differences in motivation to quit cigarette smoking or in alcohol use. Women aged 50+ were less likely to report marijuana use than women aged <50, and less likely than men to receive a positive diagnosis for alcohol abuse. Despite higher scores on measures of tobacco dependence, older smokers were less likely to be diagnosed as tobacco dependent or as having tobacco withdrawal using DSM-IV criteria. Rates of DSM-IV alcohol abuse and dependence were high in both age groups but were higher for smokers aged <50. We found no striking differences between studies in reasons for exclusion, but in both the proportion of individuals excluded due to current antidepressant use was high. Implications for the assessment and treatment of older adults are discussed.  相似文献   
106.
Models approaching consumer expectations of their water supplier from a risk perspective suggest that consumers primarily and overwhelmingly want safe drinking water supply. In this study consumer preferences in the water sector are investigated in two contrasting case studies: Cyprus, where there have been significant quantity and continuity of supply issues, and Riga, where there have been water quality issues. While water quality is undoubtedly the main priority of water consumers in Riga, in Cyprus consumers indicate that they prioritise a more reliable service even though many are sufficiently dissatisfied with water quality that they do not drink the tap water. The analysis of consumer attitudes in the two case studies suggests that when water supply is unreliable, reliability takes precedence; once it is reliable quality issues come to the fore.  相似文献   
107.
We have examined the concentrations and distributions of nonylphenol ethoxylate (NPEO) surfactants and their primary neutral metabolites in two dated sediment cores collected in 1988 and 1996 from a depositional area proximal to a wastewater treatment plant within Jamaica Bay, NY. Total NPEO concentrations ranged from >50 microg/g near the surface (4-6 cm, deposited ca. 1990) to below detection limits (<0.1 microg/g) at 50 cm depth (deposited ca. 1940). The general decrease in NPEO concentrations with increasing depth in sediment reflected increased commercial use of these compounds over the last 50 yr. NPEO ethoxymer distributions in recent sediments were dominated by NP(0-3)EO, consistent with the increased relative input of these particular ethoxymers to the estuary following the upgrade of local biological sewage treatment processes to full activated sludge in the late 1970s. NPEO ethoxymer profiles in deeper sediments were characterized by relatively higher proportions of unmetabolized, highly ethoxylated NPEOs. Depth profiles of NP1EO and NP in the upper portion of the sediment core showed evidence for in situ diagenetic conversion of NP1EO to NP. However, comparison of NPEO concentrations in selected strata from the core collected in 1996 with those in matched strata from a core collected from the same location in 1988 provided no evidence for in situ degradation of total NPEOs during the elapsed 8 yr between collection dates.  相似文献   
108.
Merits of using advanced oxidation processes such as sonolysis and photocatalysis as well as a combination of the two have been explored using model herbicides such as 2,4-dichlorophenoxy acetic acid and 2,4-dichlorophenoxypropionic acid and the chlorinated phenols 2,4-dichlorophenol and 2,4,6-trichlorophenol. Whereas sonolysis is quite effective in the initial degradation of chlorinated aromatic molecules, complete mineralization is difficult to achieve. Photocatalysis is selective toward the degradation of polar compounds but causes the build up of undesirable chemical intermediates. In contrast to sonolytic degradation, photocatalysis is very effective toward achieving complete mineralization. By simultaneously carrying out high-frequency sonolysis and photocatalysis we have succeeded in achieving faster and complete mineralization with no build up of toxic intermediates even at very low catalyst loadings. The synergy of combining the two advanced oxidation processes is discussed.  相似文献   
109.
<正>中学和大学的学生们不会有很多人把印刷传播行业作为自己的职业生涯,这也是我们行业的一个大问题。因此,面临的挑战是如何激发学生,让其考虑将印刷传播行  相似文献   
110.
This study examined the factors influencing water-based recreationists' perceptions of support and opposition towards off-shore wind energy development (OWD) on Lake Erie. Much of the proposed or future Lake Erie OWD infrastructure may either be within or adjacent to public lands, waters, and protected areas, raising concerns about the potential environmental and social impacts upon recreation stakeholders. The limited body of OWD research within the United States has suggested there are numerous factors that may influence overall perceptions of support and opposition such as political orientation and beliefs in climate change. Moreover, recent research has proposed that the perceived recreation impact of OWD may be the most important predictor of support and opposition. This study confirmed this premise and found the perceived recreation impact of OWD to be the strongest predictor of support. Results of a multiple linear regression suggested that political orientation (β?=?0.135), beliefs in the anthropogenic causation of climate change (β?=?0.207), beliefs in the occurrence of climate change (β?=?0.213), and the perceived recreation impact of OWD among water-based recreationists (β?=?0.439) were significant predictors of support for OWD on Lake Erie (R2?=?0.46). Study findings corroborated previous research which suggested that regional climate change beliefs and political attitudes may influence support for OWD. From a policy and management standpoint, study results highlight the importance of assessing and communicating recreation experience and use impacts when planning, developing, and managing OWD and related decisions in the United States.  相似文献   
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