9 research outputs found

    Role of Stearoyl-CoA desaturase-1 (SCD1) in the activation of epidermal growth factor receptor (EGFR) in lung cancer cells

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    Cancer cells activate lipogenic enzymes, including StearoylCoA Desaturase-1 (SCD1), the key enzyme that converts saturated fatty acids (SFA) into monounsaturated fatty acids (MUFA). Previously, we established that SCD1 regulates lipogenesis, cell proliferation and invasiveness in lung cancer cells, as well as tumor formation in mice. We recently reported that SCD1 modulates the PI3K/Akt pathway, a central signaling cascade, along with ERK, which are involved in the regulation of lipid biosynthesis, growth and survival of mammalian cells. Growth factor-activated tyrosine kinase receptors, such as epidermal growth factor (EGF) receptors (EGFR), are main activators of Akt and ERK signals, two cascades that are most often deranged in cancer. A hallmark of cancer is the metabolic shift towards macromolecular synthesis to support cell replication. SCD1 expression increases in cancer cells. The molecular mechanisms by which SCD1 regulates the biological phenotype of cancer cells is still unknown. The poor prognosis and ineffective treatments of some cancers, such as lung cancer, calls for better understanding of their mechanisms and for finding novel targets that, like SCD1, modulate the Akt and ERK pathways. Here we provide evidence that SCD1 activity controls the activation of EGFR and its downstream signaling targets, Akt and ERK. Using H460 human lung cancer cells, we observed that the activating phosphorylation of Tyr1068 and Tyr1086 residues in EGFR upon EGF stimulation was markedly impaired when SCD1 activity was blocked with CVT-11127, a novel small molecule SCD inhibitor. In addition, supplementation with oleic acid, the product of SCD1, restored EGF-induced phosphorylation of EGFR but not the full phosphorylation of Akt. Finally, abrogation of SCD1 dramatically altered distribution of rafts and non-raft domains, suggesting that the regulation of EGFR function by SCD1 may involve the alteration of membrane lipid domains. All results are representative of 3 separate experiments. In conclusion, our data indicate that SCD1 may coordinate the regulation of lipid biosynthesis and the transduction signals that control cancer cell metabolism, proliferation, survival and tumorigenesis by modulating EGFR activation, which subsequently modifies the Akt and ERK signaling platforms. Our findings also suggest SCD1 is a potential target for novel pharmacological interventions in lung cancer.M.S.Includes bibliographical referencesby Mary Nashe

    GIS and geotechnical mapping of expansive soil in Toshka region

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    AbstractThis paper presents the results of a subsurface site investigation that was performed to characterize different soil and rock formations along Sheikh Zayed canal with particular emphasis on the swelling characteristics of the clays in that area. Site-specific empirical correlations were developed to predict the clay swelling potential and pressure from simple and economic laboratory test results. The data were input into a Geographic Information System (GIS) framework to provide interactive maps that show the spatial distribution of the variables and identify their characteristics. These maps are then used to easily identify the values of swelling pressure/potential at various locations. This research provides a tool that is based on simple index tests that can be used to provide data that otherwise would require elaborate and costly investigations; the GIS framework allows storing, retrieving and updating these data easily to assist taking supported decisions dynamically

    Maxwell-f(Q) Theory

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    Exploring the four-dimensional AdS black hole is crucial within the framework of the AdS/CFT correspondence. In this research, four-dimensional stationary and rotating AdS solutions in the framework of the (Formula presented.) gravitational theory are investigated, considering the charged scenario. Author\u27s emphasis is on the power-law ansatz, which consistent with observations and is deemed the most viable. Because this solution does not have an uncharged version or relate to general relativity, it falls into a new category, which derives its features from changes in non-metricity and incorporates the Maxwell domain. The singularities of such a solution are analyzed, computing all the quantities of different curvature and non-metricity invariants. Author\u27s results indicate the presence of a central singularity, albeit with a softer nature compared to standard non-metricity or Einstein general relativity, attributed to the influence of the effect of (Formula presented.). Several physical characteristics of black hole from thermodynamics perspective and demonstrate the existence of an outer event horizon in addition to the inner Cauchy horizons are examined. However, under the conditions of sufficiently large electric charge, a naked singularity emerges. Finally, a class of rotating black hole in four-dimensional (Formula presented.) gravity that are asymptotically anti-de Sitter charged is derived

    An investigation and study from the chapter of divorce of the patient to the chapter of seizure from the book "Tuhfat al-Akhayyar Ala al-Dur al-Mukhtar" which was written by Abu al-Safa Burhan al-Din Ibrahim bin Mustafa al-Halabi

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    Bu çalışma İstanbul Sebahattin Zaim üniversitesinde İslami ilimler programı yüksek lisans derecesi kazanmak için takdim edilmiş ilmi bir çalışmadır. Tez konumuzun başlığı Ebü'l-Sefâ Burhânüddîn İbrâhîm b. Mustafa el-Halebî'nin Tuhfetü'l-Ahyâr alâ Dürrü'l-mu'târ eserinden "talâkul merîz babından istîlâ babına kadar olan bölümün tahkik ve incelemesini teşkil etmektedir. Tuhfetü'l-Ahyâr, Muhammed b. Abdullah et-Timurtaşî'nin Tenvîrü'l-eb'âr adlı eserine Haskefî'nin ed-Dürrü'l-mu'târ adıyla yazdığı şerh üzerine yazılmış bir hâşiyedir. El-Halebî haşiyesinde kapalı ibareleri açıklamış, problemli yerlere notlar düşmüş, bazen tashih bazen beyan bazense tasvipte bulunmuştur. Halebî'nin bu haşiyesi bu kitap üzerine yazılmış haşiyelerin en önemlilerindendir. Arzu edilen amaca yönelik en faydalı, kabul gören bir düzene sahip, mümkün olduğunca doğru görüşler belirtilmiştir. Yazar, eserindeki itiraz tashih ve düzeltmelerde ulemaya karşı saygısını korumuştur. Tahkik edilen bölüme talâk kitabından bir miktar, ricat, îlâ, Hulu, zihar, li'ân, anin ve iddet bablarından ayrıca itk kitabından da bir bölüm ilave etmiştir. Çalışmamı iki ana bölüme ayırdım; Bir: inceleme İki: seçili bölümün tahkiki Tüm bunları inşallah yeri geldikçe açıklayacağım. Yüce Rabbimden takdim ettiğim çalışmamın bana fayda sağlamasını niyaz ediyorum. İmam el-Halebî'ye ilim ve ilim ehline sağladığı katkılardan ötürü mükafatların en hayırlısını bahşetmesini diliyorum. Rabbimden bu çalışmamı yazarın Murad ettiği incelikleri tespit ederek itmam etme konusunda yardım talep ediyorum. Rabbul âlemin her şeye gücü yeten ve her şeyin sahibidir.This Scientific Thesis Was Prepared In An Effort To Obtain A Master's Degree In The Islamic Studies Program At The Istanbul Sabahattin Zaim University. It Is Titled "An Investigation And Study From The Chapter Of Divorce Of The Patient To The Chapter Of Seizure" From The Book "Tuhfat Al-Akhayyar Ala Al-Dur Al-Mukhtar" Which Was Written By Abu Al-Safa Burhan Al-Din Ibrahim Bin Mustafa Al-Halabi. Tuhfat Al-Akhayyar Is An Annotation Placed On "Al-Durr Al-Mukhtar" By Ala Al-Din Al-Hasakfi In His Commentary On Tanwir Al-Absar By Muhammad Al-Tamrtashi. Al-Halabi Has Explained In His Annotation The Ambiguous Phrases And Commented On The Touchy Issues As Well As Added Some Corrections. That Is Why Al-Habibi's Explanation Was One Of The Most Important Annotations To This Book. It Served A Great Purpose And Coordinated An Acceptable Method Of Making Corrections. He Was As Polite And Humble With The Scholars In His Objection, Criticism And Correction. This Investigative Thesis Has Included Some Of The Divorce Chapter, The Chapters Of Rajah, Lla, Khule, Zihar, Li'an. Eanan, Iddah And Some Of The Manumission Chapter. I Divided The Thesis Into Two Parts. First, Being The Study Of The Content And The Second Being The Investigation Of The Assigned Section. This Will Be Explained In Detail Within The Thesis, Allah Willing. Finally, I Ask Allah Almighty To Benefit Me From What I Have Endeavored Upon, And To Reward Imam Al-Halabi For His Knowledge The Best Reward, And To Help Me To Produce This Thesis Accurately As It Was Desired By It's Author

    Physical-chemical Properties of Aqueous TBAOH Solution for Gas Hydrates Promotion

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    AbstractGas hydrates attract the attention of many industries for various potential applications such as gas separation and storage. To industrialize the gas hydrate technology, rapid hydrate formation at mild conditions is crucial. Chemical additives such as ionic liquids were investigated for hydrate promotion. The knowledge of physical-chemical properties of ionic liquids is crucial in development of gas hydrate technology in industry as these fundamental properties determined the hydrate formation rate. This work measures the density, pH, electrical conductivity, and surface tension of aqueous tetrabutylammonium hydroxide solutions. The concentrations were chosen to cover the common hydrate promotion range of 0.001-10 wt%. The results showed high dependence of the studied properties on the concentration. pH and electrical conductivity were increased with increase of TBAOH concentration conversely to density and surface tension. The amount of CO2 consumed to form the hydrate was measured at a pressure of 35bar and a temperature 274.15. Significant increase of CO2 consumption in the presence of TBAOH solutions was observed. However, as the concentration increased, more CO2 was consumed

    Gas Hydrate Equilibrium Measurement of Methane + Carbon Dioxide + Tetrahydrofuran+ Water System at High CO2 Concentrations

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    AbstractApplication of gas hydrate in separation of carbon dioxide (CO2) form nitrogen in Carbon Capture and Storage (CCS) chain is recently studied by many researchers. Tetrahydrofuran (THF) is suggested as promoter for this process. The same process can be suggested for separation of CO2 from methane (CH4) for gas treatment and sweetening, especially for high CO2 content mixtures such as landfill gas. The first step in development of such process is understanding of the phase boundary of this mixture at different pressure-temperature condition and gas/liquid composition. In this work, gas hydrate phase boundary of CH4, CO2, THF and water at different pressure from 4.5 to 8.1 MPa is experimentally measured. CO2 mole fraction in gas phase is fixed at 0.7 and THF concentration in the liquid phase set at 0.03 mole fraction. Results show that presence of THF in the mixtures shift the phase boundary to the lower pressure / higher temperature condition. This effect is favorable for industrial applications

    RAMAN AND INFRARED SPECTRA, CONFORMATIONAL STABILITY, BARRIERS TO INTERNAL ROTATION. AB INITIO CALCULATIONS AND I0I_{0} STRUCTURE FOR VINYL SILYL FLUORIDE

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    Author Institution: Department of Chemistry, University of Missouri-Kansas CityThe Raman (3250 to 10cm110 cm^{-1}) and infrared (3250 to 40cm140 cm^{-1}) spectra of the gaseous and solid vinyl silyl fluoride (CH2CHSiH2FCH_{2}CHSiH_{2}F), have been recorded. From the far infrared spectrum of the gas, the fundamental asymmetric torsions for both the cis and gauche conformers have been observed at 102.34 and 86.56cm186.56 cm^{-1}, respectively, with each having several excited state transitions falling to lower frequencies. From these transitions, the potential function to internal rotation has been determined with the following values: V1,V2,V3,V4V_{1}, V_{2}, V_{3}, V_{4} and V6V_{6}, with the gauche conformer thermodynamically preferred by 82±20cm182 \pm 20 cm^{-1}. The cis to gauche, gauche to gauche, and gauche to cis barriers and 702 (8.40 kJ/mol), 588 (7.04 kJ/mol) and cm1cm^{-1} (7.42 kJ/mol), respectively. Variable temperature (105-105 to 150C-150^{\circ} C) studies of the infrared spectra of the sample dissolved in liquid krypton have been carried out. From these data, the enthalpy difference has been determined to be 76cm176 cm^{-1} (0.91 kJ/mol). Additionally, ab initio calculations have been carried out utilizing the 6-31G (d) basis sets to obtain the conformational stability, barriers to internal rotation and optimized structural parameters

    RAMAN AND INFRARED SPECTRA, CONFORMATIONAL STABILITY, AB INITIO CALCULATIONS AND VIBRATIONAL ASSIGNMENTS FOR ETHYL FLUOROSILANE

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    Author Institution: Department of Chemistry, University of Missouri-Kansas CityThe infrared (3500 to 30cm130 cm^{-1}) spectra of gaseous and solid and the Raman (3500 to 10cm110 cm^{-1}) spectra of the liquid with quantitative depolarization ratios and solid ethyl fluorosilane, FSiH2CH2CH3FSiH_{2}CH_{2}CH_{3}, have been recorded. These data indicate that two conformers are present in the fluid states but only one conformer is present in the annealed crystalline state. The mid-infrared spectra of the sample dissolved in liquefied xenon as a function of temperature (-100 to 55C-55^{\circ} C) have been recorded, Utilizing conformer pairs a 1022 (gauche), 1010 (trans), 719 (gauche), 727 (trans), and 693 (trans) cm1cm^{-1} the enthalpy difference has been determined to be 101±18cm1(1.21±0.22101 \pm 18 cm^{-1} (1.21 \pm 0.22 kJ/mol) with the gauche conformer the more stable species and the one remaining in the solid. The optimized geometries, conformational stabilities, harmonic force fields, infrared intensities, Raman activities, depolarization ratios, and vibrational frequencies will be reported for both conformers from MP2/631GMP2/6-31G^{\ast} ab initio calculations. The gauche conformer is predicted to be the more stable rotamer from ab initio calculations in agreement with the experimental results

    Computation of General Inner-Outer and Spectral Factorizations

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    In this paper, we solve two problems in linear systems theory: the computation of the inner-outer and spectral factorizations of a continuous-time system considered in the most general setting. We show that these factorization problems rely essentially on solving for the stabilizing solution a standard algebraic Riccati equation of order usually much smaller than the McMillan degree of the transfer function matrix of the system. The proposed procedures are completely general, being applicable for a polynomial/proper/improper system whose transfer function matrix could be rank deficient and could have poles/zeros on the imaginary axis or at infinity. As an application we discuss the extension to the case of rational matrices of the complete orthogonal decomposition of a constant matrix. Numerical refinements and examples illustrating the proposed approach, are discussed in detail
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