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31.
de Jager T Pelzer T Müller-Botz S Imam A Muck J Neyses L 《The Journal of biological chemistry》2001,276(30):27873-27880
We have previously shown that the myocardium is a target tissue for estrogen. Here, we have identified rapid non-nuclear estrogen effects on the expression of the early growth response gene-1 (Egr-1) in cardiomyocytes. Egr-1 mRNA and protein were rapidly and strongly induced by estrogen in an estrogen receptor-dependent manner via the extracellular signal-regulated kinase, ERK1/2. A promoter analysis study of a 1.2-kilobase Egr-1 promoter fragment revealed that the serum response elements (SREs) but not the estrogen response elements or AP-1 sites are responsible for Egr-1 induction by estrogen, identifying a novel mechanism of estrogen receptor-dependent gene activation in the myocardium. Both estrogen receptor-alpha and -beta induced the Egr-1 promoter via the SREs as well as an artificial promoter consisting of only five SREs in cardiomyocytes. Electrophoretic mobility shift assays showed that a protein complex containing serum response factor or an antigenically related protein was recruited to the SREs by estrogen treatment of primary cardiomyocytes. The recruitment of the protein complex was inhibited by the specific estrogen receptor antagonist ICI 182,780 as well as the MEK inhibitor PD 98059. Taken together, these results identify SREs as important promoter control elements for an estrogen receptor-dependent mechanism of gene activation in the myocardium. 相似文献
32.
Ibrahim R. Shimi Moustafa S. Nour El Dein Gamal M. Imam 《Archives of microbiology》1961,39(3):292-297
Summary The formation of fat from citric, succinic, fumaric and malic acids by Penicillium spinulosum has been investigated. Sodium arseite, -sulfonic propionic acid and mono-iodoacetate was found to control unfavourably the formation of fat from the organic acids by the preformed pellets of the organism. Moreover, iodoacetate reduced the mean molecular weight of the component fatty acids. The -sulfonic propionic acid though reduced the yields of fat yet the ratio fat/100 g of acid consumed was not markedly altered by this compound. A modified chromatographic method was described for the assay of different acids.With 3 Figures in the text 相似文献
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Imam KA 《Reviews in urology》2004,6(Z1):S38-S44
Urinary incontinence is a major health challenge for primary care physicians. Unfortunately, the majority of incontinent patients remain untreated. Primary care physicians are ideally positioned to screen for and manage urinary incontinence. A knowledge of basic micturition physiology is important for the physician to accurately identify the cause of incontinence and arrive at the correct treatment course. To this end, this article reviews the physiology of the lower urinary tract, describes the clinical types of urinary incontinence, and outlines a stepwise approach for the primary care physician to the basic evaluation and management of patients with this condition. 相似文献
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Faisal Khan KM Laurie GW McCaffrey TA Falcone DJ 《The Journal of biological chemistry》2002,277(16):13778-13786
Degradation of the extracellular matrix leads to the release of fragments, which elicit biological responses distinct from intact molecules. We have reported that alpha1:Ser(2091)-Arg(2108), a peptide derived from the alpha1-chain of laminin-1, triggers protein kinase C-dependent activation of MAPK(erk1/2), leading to the up-regulation of macrophage urokinase type plasminogen activator and matrix metalloproteinase (MMP)-9 expression. Since intact laminin-1 failed to trigger these events, we hypothesized that alpha1:Ser(2091)-Arg(2108) is cryptic or assumes a conformation not recognized by macrophages. Here we demonstrate that elastase cleavage of laminin-1 generates fragments, which stimulate proteinase expression by RAW264.7 macrophages and peritoneal macrophages. In contrast, fragments generated by MMP-2, MMP-7, or plasmin had no effect on macrophage proteinase expression. Elastase-generated laminin-1 fragments were fractionated by heparin-Sepharose chromatography. Heparin-binding fragments stimulated macrophages' proteinase expression severalfold greater than nonbinding fragments. The heparin binding fragments reacted with antibodies directed against regions of the alpha1-chain including alpha1:Ser(2091)-Arg(2108) and the globular domain. A peptide from the first loop of the globular domain (alpha1:Ser(2179)-Ser(2198)) triggered the phosphorylation of MAPK(erk1/2) and stimulated the expression of macrophage urokinase type plasminogen activator and MMP-9. Moreover, a heparin-binding fraction isolated from an aortic aneurysm contained fragments of alpha1-chain and stimulated macrophages' proteinase expression. Based on these data, we conclude that cryptic domains in the COOH-terminal portion of the alpha1-chain of laminin are exposed by proteolysis and stimulate macrophages' proteinase expression. 相似文献
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Daniel Tom-Aba Adeniyi Olaleye Adebola Tolulope Olayinka Patrick Nguku Ndadilnasiya Waziri Peter Adewuyi Olawunmi Adeoye Saliu Oladele Aderonke Adeseye Olukayode Oguntimehin Faisal Shuaib 《PloS one》2015,10(6)
The recent outbreak of Ebola Virus Disease (EVD) in West Africa has ravaged many lives. Effective containment of this outbreak relies on prompt and effective coordination and communication across various interventions; early detection and response being critical to successful control. The use of information and communications technology (ICT) in active surveillance has proved to be effective but its use in Ebola outbreak response has been limited. Due to the need for timeliness in reporting and communication for early discovery of new EVD cases and promptness in response; it became imperative to empower the response team members with technologies and solutions which would enable smooth and rapid data flow. The Open Data Kit and Form Hub technology were used in combination with the Dashboard technology and ArcGIS mapping for follow up of contacts, identification of cases, case investigation and management and also for strategic planning during the response. A remarkable improvement was recorded in the reporting of daily follow-up of contacts after the deployment of the integrated real time technology. The turnaround time between identification of symptomatic contacts and evacuation to the isolation facility and also for receipt of laboratory results was reduced and informed decisions could be taken by all concerned. Accountability in contact tracing was ensured by the use of a GPS enabled device. The use of innovative technologies in the response of the EVD outbreak in Nigeria contributed significantly to the prompt control of the outbreak and containment of the disease by providing a valuable platform for early warning and guiding early actions. 相似文献
39.
An -amylase (E.C. 3.2.1.1.) secreted byLactobacillus amylovorus was partially purified and characterized. This high-molecular-weight enzyme [Imam SH, Burgess-Cassler A, Côté GL, Gordon SH, Baker FL (1991) Curr Microbiol 22:365–370] was quantified with a clinical -amylase assay adapted to a microplate format. It was isolated from concentrated cell-free culture medium by ammonium sulfate precipitation, ion exchange, and hydrophobic interaction chromatographies. The enzyme was not particularly thermostable, but like three other microbial -amylases tested for comparison, was renaturable following treatment with SDS and heat. The pH optimum and pI were 5.5±0.5 and 5.0, respectively; its temperature optimum was 60–65°C, and the molecular weight on SDS gels was 140±10 kDa. 相似文献
40.
Faisal?Thayyullathil Siraj?Pallichankandy Anees?Rahman Jaleel?Kizhakkayil Shahanas?Chathoth Mahendra?Patel Sehamuddin?GaladariEmail author 《Journal of molecular signaling》2013,8(1):2