Relevant bibliographies by topics / Phospholipids

Academic literature on the topic 'Phospholipids'

Author: Grafiati
Published: 4 June 2021
Last updated: 29 July 2024

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Journal articles on the topic "Phospholipids"

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Von Seg Esser, L. K., M. Tönz, B. Leskosek, and M. Turina. "Evaluation of Phospholipidic Surface Coatings ex-vivo." International Journal of Artificial Organs 17, no. 5 (May 1994): 294–300. http://dx.doi.org/10.1177/039139889401700507.

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To evaluate the thromboresistant properties of phospholipidic surface coatings mimicking the lipid surface of blood cells, we studied four different types of phospholipids bound onto PVC tubings in comparison to uncoated as well as heparin bonded controls. The samples analyzed included diacetylenic phospholipid coated as a monomeric treatment (A), diacetylenic phospholipid polymerised prior to being coated (B), and two types of polymeric phospholipids made using methacrylate containing monomers (C and D). A bovine (bodyweight 67 ± 3 kg) left heart bypass model (pump flow 3.2 ±0.1 l/min) was selected and the surfaces were exposed to the blood stream up to 360 min without systemic heparinization. Thereafter another set of samples was exposed to stagnant blood over 20 min. Besides hemodynamic, hematologic and biochemical analyses, the macroscopic appearance of 119 blood exposed surface samples was graded semiquantitatively on a scale of 0 to 10: no macroscopic deposits = grade 0, 1 spot (1 mm diameter) = grade 1, 2 spots = grade 2, 5 or more spots = grade 5, up to 10% of the surface covered with clots = grade 6, 100% covered = grade 10 (p<0.05=∗): mean grade of deposits was 0.0 ± 0.0 for segments perfused and 0.0 ± 0.0 for segments exposed to stagnant blood with surfaces exposing to the blood either heparin, phopholipid A, or phospholipid B (NS). Phospholipids C and D were graded 0.0 ± 0.0 if perfused and 0.7 ± 1.2 if exposed to stagnant blood. Uncoated PVC control tubings however were graded 0.2 ± 0.8 for segments perfused and 2.7 ± 3.0 for segments exposed to stagnat blood (p<0.05 in comparison to all surfaces coated with phospholipids or heparin if perfused and if exposed to stagnant blood). Hence phospholipidic surface coatings expose significant antithrombotic properties which out perform todays standard for tubings in clinical perfusion (uncoated PVC).
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Rudzite, Vera, Edite Jurika, Gabriele Baier-Bitterlich, Helmut Wachter, and Dietmar Fuchs. "Effect of Sepiapterin, 7,8-Dihydrobiopterin, 5,6,7,8-Tetrahydrobiopterin and Xanthopterin on Cholesterol and Phospholipid Content and Phospholipid Biosynthesis in vitro." Pteridines 6, no. 2 (May 1995): 69–73. http://dx.doi.org/10.1515/pteridines.1995.6.2.69.

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Summary Incorporation of fatty acids into phospholipids has been investigated using samples of rat live tissue homogenate, Krebs-Ringer-phosphate buffer (pH = 7A) containing 0.3% albumin, farry acid mixture and glycerol. The addition of sepiapterin, 7,8-dihydrobiopterin and 5.6.7.8-tetrahydrobiopterin (5 and 30 pmol g wet weight) to incubation medium induced a decrease of saturated (stearic acid) and an increase of polyunsaturated (arachidonic acid) fatty acids incorporation into phospholipids. Cholesterol content decreased, but phospholiplid content did not change in samples containing sepiapterin, 7,8-dihydrobiopterin and 5,6,7,8-tetrahydrobiopterin. No changes of fatty acid incorporation into phospholipids as well as of the content of cholesterol and phospholipids were observed in samples after the addition of xanthopterin (4 and 20 nmol/g wet weight) to incubation medium for phospholipid biosynthesis in vitro. The observations made by incubation with 7,8-dihydrobiopterin, 5,6,7,8-tetrahydrobiopterin and sepiapterin where in opposite to those made earlier employing neopterin and using the same incubation procedure.
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Pan, F. G., J. Liu, J. X. Yang, J. R. Ren, Y. Y. Sun, P. Z. Li, E. Q. Yang, X. M. Chen, and B. Q. Liu. "Research progress on the genesis and removal methods of non-hydratable phospholipids from vegetable oils." Grasas y Aceites 75, no. 1 (April 10, 2024): e543. http://dx.doi.org/10.3989/gya.0325231.

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Vegetable oil phospholipids can be divided into hydratable phospholipids (HP) and non-hydratable phospholipids (NHP). The general process of alkali refining or hydration degumming can remove most of the phospholipids, and the rest is mainly non-hydratable phospholipids. A non-hydratable phospholipid has obvious hydrophobicity, which cannot be completely removed even after 16 times of washing, so the non-hydratable phospholipid is the main research target of vegetable oil degumming. In order to better understand and study the non-hydratable phospholipids, the chemical composition and origin of non-hydratable phospholipids in vegetable oil are discussed. The advantages and disadvantages of these various detection and removal methods are analyzed in this paper.
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Cuvelier, I., J. Steinmetz, T. Mikstacki, and G. Siest. "Variations in total phospholipids and high-density lipoprotein phospholipids in plasma from a general population: reference intervals and influence of xenobiotics." Clinical Chemistry 31, no. 5 (May 1, 1985): 763–66. http://dx.doi.org/10.1093/clinchem/31.5.763.

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Abstract The influence of different factors on variations in the concentrations of total phospholipids and high-density-lipoprotein (HDL) phospholipids in plasma was studied in a presumably healthy population of 2000 subjects, four to 70 years old. Age is the major factor associated with variation of total phospholipids. In females, this is due in part to age-related changes in hormonal status. The use of oral contraceptives affects only HDL phospholipid values. Use of tobacco does not influence plasma phospholipid values, but alcohol consumption increases values for both total and HDL phospholipids. We propose reference intervals for total plasma phospholipids and HDL phospholipids, adjusted for age and sex. Screening for lipid status can now include determinations of phospholipids as well as cholesterol and triglycerides.
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Vial, Thomas, Wei-Lian Tan, Eric Deharo, Dorothée Missé, Guillaume Marti, and Julien Pompon. "Mosquito metabolomics reveal that dengue virus replication requires phospholipid reconfiguration via the remodeling cycle." Proceedings of the National Academy of Sciences 117, no. 44 (October 21, 2020): 27627–36. http://dx.doi.org/10.1073/pnas.2015095117.

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Dengue virus (DENV) subdues cell membranes for its cellular cycle by reconfiguring phospholipids in humans and mosquitoes. Here, we determined how and why DENV reconfigures phospholipids in the mosquito vector. By inhibiting and activating the de novo phospholipid biosynthesis, we demonstrated the antiviral impact of de novo–produced phospholipids. In line with the virus hijacking lipids for its benefit, metabolomics analyses indicated that DENV actively inhibited the de novo phospholipid pathway and instead triggered phospholipid remodeling. We demonstrated the early induction of remodeling during infection by using isotope tracing in mosquito cells. We then confirmed in mosquitoes the antiviral impact of de novo phospholipids by supplementing infectious blood meals with a de novo phospholipid precursor. Eventually, we determined that phospholipid reconfiguration was required for viral genome replication but not for the other steps of the virus cellular cycle. Overall, we now propose that DENV reconfigures phospholipids through the remodeling cycle to modify the endomembrane and facilitate formation of the replication complex. Furthermore, our study identified de novo phospholipid precursor as a blood determinant of DENV human-to-mosquito transmission.
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Jackowski, Suzanne, and Charles O. Rock. "Phospholipids and phospholipid metabolism." Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids 1831, no. 3 (March 2013): 469–70. http://dx.doi.org/10.1016/j.bbalip.2013.01.001.

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Ventura, Raúl, Inma Martínez-Ruiz, and María Isabel Hernández-Alvarez. "Phospholipid Membrane Transport and Associated Diseases." Biomedicines 10, no. 5 (May 23, 2022): 1201. http://dx.doi.org/10.3390/biomedicines10051201.

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Phospholipids are the basic structure block of eukaryotic membranes, in both the outer and inner membranes, which delimit cell organelles. Phospholipids can also be damaged by oxidative stress produced by mitochondria, for instance, becoming oxidized phospholipids. These damaged phospholipids have been related to prevalent diseases such as atherosclerosis or non-alcoholic steatohepatitis (NASH) because they alter gene expression and induce cellular stress and apoptosis. One of the main sites of phospholipid synthesis is the endoplasmic reticulum (ER). ER association with other organelles through membrane contact sites (MCS) provides a close apposition for lipid transport. Additionally, an important advance in this small cytosolic gap are lipid transfer proteins (LTPs), which accelerate and modulate the distribution of phospholipids in other organelles. In this regard, LTPs can be established as an essential point within phospholipid circulation, as relevant data show impaired phospholipid transport when LTPs are defected. This review will focus on phospholipid function, metabolism, non-vesicular transport, and associated diseases.
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BRIGHTON, Timothy A., Yan-Ping DAI, Philip J. HOGG, and Colin N. CHESTERMAN. "Microheterogeneity of beta-2 glycoprotein I: implications for binding to anionic phospholipids." Biochemical Journal 340, no. 1 (May 10, 1999): 59–67. http://dx.doi.org/10.1042/bj3400059.

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Considerable interest is currently focused on the interactions of beta-2 glycoprotein I (β2GPI) and anti-phospholipid antibodies with anionic phospholipids in an attempt to understand the association between these antibodies and clinical diseases such as thrombosis. The interactions of β2GPI and anionic phospholipids have only been characterized partially, and the physiological role of this glycoprotein remains uncertain. In this study we have explored in detail the physical and phospholipid-binding characteristics of a number of β2GPI preparations. We have found (i) that perchloric acid-purification methods are damaging to β2GPI during purification, (ii) that the dissociation constants of the various preparations for phosphatidylserine vary between 0.1-2 μM and are considerably weaker than previously reported, (iii) that considerable differences in affinity of the various β2GPI preparations for anionic phospholipids are obtained when comparing anionic phospholipids immobilized to a solid-phase versus phospholipid assembled in unilamellar vesicles, (iv) that the integrity of the fifth domain of β2GPI is important for binding immobilized anionic phospholipid but not especially important in binding vesicular anionic phospholipid, and (v) that β2GPI preparations with differing isoelectric species content bind anionic phospholipids differently, suggesting that varying glycosylation and/or protein polymorphisms impact upon phospholipid binding. These results highlight the importance of assessing the determinants of the interaction of β2GPI with anionic phospholipids assembled in unilamellar vesicles.
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Hatch, Grant M. "Cell biology of cardiac mitochondrial phospholipids." Biochemistry and Cell Biology 82, no. 1 (February 1, 2004): 99–112. http://dx.doi.org/10.1139/o03-074.

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Phospholipids are important structural and functional components of all biological membranes and define the compartmentation of organelles. Mitochondrial phospholipids comprise a significant proportion of the entire phospholipid content of most eukaroytic cells. In the heart, a tissue rich in mitochondria, the mitochondrial phospholipids provide for diverse roles in the regulation of various mitochondrial processes including apoptosis, electron transport, and mitochondrial lipid and protein import. It is well documented that alteration in the content and fatty acid composition of phospholipids within the heart is linked to alterations in myocardial electrical activity. In addition, reduction in the specific mitochondrial phospholipid cardiolipin is an underlying biochemical cause of Barth Syndrome, a rare and often fatal X-linked genetic disease that is associated with cardiomyopathy. Thus, maintenance of both the content and molecular composition of phospholipids synthesized within the mitochondria is essential for normal cardiac function. This review will focus on the function and regulation of the biosynthesis and resynthesis of mitochondrial phospholipids in the mammalian heart.Key words: phospholipid, metabolism, heart, cardiolipin, mitochondria.
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Rudzite, Vera, Edite Jurika, Matthias Jäger, and Dietmar Fuchs. "Impairment of Lipid Metabolism Due to Deficiency of Pyridoxal-5-phosphate and/or Activated Immune system: its Interpretation." Pteridines 11, no. 4 (November 2000): 107–20. http://dx.doi.org/10.1515/pteridines.2000.11.4.107.

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Abstract Impairment of lipid metabolism due to excess metabolite accumulation induced by pyridoxal-5-phosphate (P-5-P)-deficiency and/or stimulated immune system has been studied and interpreted. Decreased amounts of phospholipids as well as deviations in phospholipid classes and fatty acid composition of phospholipids have been demonstrated due to kynurenine accumulation in the blood of P-5-P-deficient cardiovascular patients and white rats as well as in cardiovascular patients with activated immune system identified by an increased neopterin concentration in the blood (dilated cardiomyopathy). The addition of P-5-P to the incubation medium for phospholipid biosynthesis in vitro did not change fatty acid incorporation into phospholipids, whereas it normalised fatty acid incorporation into phospholipids in liver homogenates received from P-5-P-deficient rats: The addition of kynurenine, neopterin and noradrenalin (accumulated m isolated heart tissue after addition of kynurenine and neopterin to incubation medium for isolated heart) to incubation medium for phospholipid biosynthesis in vitro induced an increase of saturated and a decrease of polyunsaturated fatty acid incorporation into phospholipids. These changes in fatty acid incorporation into phospholipids were followed by increased cholesterol concentrations in samples and an increased cholesterol/phospholipid ratio. Our results suggest that these changes in lipids are characteristic for decreased membrane fluidity, depressed cell cycle and lowered possibility of phospholipids to keep cholesterol in solution. P-5-P-deficiency is also accompanied with excess accumulation of homocysteine in the blood. The addition of L-homocysteine to the incubation medium for phospholipid biosynthesis in vitro was followed by inverse changes in fatty acid incorporation into phospholipids when compared with kynurenine, neopterin and noradrenalin. L-homocysteine induced a decrease of saturated and an increase of polyunsaturated fatty acid incorporation into phospholipids. The cholesterol concentration decreased in samples and the cholesterol/ phospholipid ratio decreased, too . These findings suggest that changes in lipids induced by L-homocysteine are characteristic for increased membrane fluidity and stimulated cell cycle. In this study, we have observed a similar effect to L-homocysteine effect when L-homocysteine, L-tryptophan and 5,6,7,8-tetrahydrobiopterin were added to the incubation medium for phospholipid biosynthesis in vitro. The comparison of our results with data from the literature allows to suggest that excess metabolite accumulation due to activated formation and inactivated catabolism of it plays a significant role in quantitative and qualitative changes of lipids, especially phospholipids, and therefore participates in the regulation of membrane fluidity, cell cycle of normal and malignant cells as well as in keeping cholesterol in the state of solution.
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Dissertations / Theses on the topic "Phospholipids"

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Carmical, Jennifer, and Stacy D. Brown. "The Impact of Phospholipids and Phospholipid Removal on Bioanalytical Method Performance." Digital Commons @ East Tennessee State University, 2016. https://doi.org/10.1002/bmc.3686.

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Phospholipids (PLs) are a component of cell membranes, biological fluids and tissues. These compounds are problematic for the bioanalytical chemist, especially when PLs are not the analytes of interest. PL interference with bioanalysis highly impacts reverse-phase chromatographic methods coupled with mass spectrometric detection. Phospholipids are strongly retained on hydrophobic columns, and can cause significant ionization suppression in the mass spectrometer, as they out-compete analyte molecules for ionization. Strategies for improving analyte detection in the presence of PLs are reviewed, including in-analysis modifications and sample preparation strategies. Removal of interfering PLs prior to analysis seems to be most effective at moderating the matrix effects from these endogenous cellular components, and has the potential to simplify chromatography and improve column lifetime. Products targeted at PL removal for sample pre-treatment, as well as products that combine multiple modes of sample preparation (i.e. Hybrid SPE), show significant promise in mediating the effect on PL interference in bioanalysis.
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Zschörnig, Kristin. "Massenspektrometrische Untersuchungen an Spermien-Phospholipidmembranen." Doctoral thesis, Universitätsbibliothek Leipzig, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-154791.

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Fettleibigkeit und Adipositas haben in den letzten Jahren weltweit drastisch zugenommen. Die Fettleibigkeit geht nicht nur mit einer verringerten Lebensqualität einher, sondern ist auch mit verschiedenen Folgeerkrankungen, wie kardiovaskulären Erkrankungen (z.B. Arteriosklerose) und metabolische Erkrankungen (z.B. Diabetes) assoziiert. Vorliegende Studien belegen einen Zusammenhang zwischen Diabetes und männlicher Infertilität. In der vorliegenden Arbeit wurden daher die Spermienmembran wie auch das Seminalplasma (SP) mittels matrix-assisted laser desorption and ionisation time-of-flight Massenspektrometrie (MALDI-TOF MS) analysiert, um mögliche Lipid-Biomarker für die Fertilität bzw. Infertilität zu finden. Dafür wurde zunächst die MALDI-TOF MS Methode mit relevanten Standardlipiden optimiert. Anschließend konnte sowohl das Phospholipidmuster des SP mit dem Spermien verglichen werden als auch die Spermienlipide von normalgewichtigen und fettleibigen Probanden. Durch diese Analyse konnte das Phosphatidylcholin/Lysophosphatidylcholin (PC/LPC)-Verhältnis, aber auch ein stark erhöhter Sphingomyelin (SM)-Anteil bei den fettleibigen Probanden als Qualitätsmarker gefunden werden. Des Weiteren wurden im Rahmen dieser Arbeit murine Spermien aus dem Caput und dem Cauda der Epididymis mittels MALDI-TOF MS analysiert und das Phospholipidmuster miteinander verglichen. Es konnte damit gezeigt werden, dass die murinen Spermien einen wesentlich höheren Anteil an Stearinsäureresten aufweisen, die humanen Spermien hingegen vor allem durch Palmitinsäurereste charakterisiert sind. In den Spermienmembranen aus dem Cauda und dem Caput gab es wesentliche Unterschiede im Phospholipidmuster. Spermienmembranen aus dem Caput besitzen einen hohen Anteil an PC und Phosphatidylethanolamin (PE). Die Spermienmembranen aus dem Cauda hingegen enthalten mehr SM, und auch einen höheren Anteil an LPCs und Formyl-LPC. Diese Arbeit konnte somit zeigen, dass die Reifungsprozesse in der Epididymis auch die Phospholipid-Zusammensetzung betreffen.
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Pham, Quoc Dat. "Effects of Oxidized Phospholipids and Heavy Water on the Structure of Phospholipid Bilayer Membranes." Thesis, Umeå universitet, Kemiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-57935.

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Murphy, Elizabeth J. "'3'1p NMR studies of phospholipids and phospholipid metabolism and in vivo and in vitro." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315707.

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Meca, Julien. "Etude de l’interaction entre un module de polarité Rho GTPase et l’environnement membranaire chez Saccharomyces cerevisiae." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0204.

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La polarité cellulaire, organisation asymétrique du matériel cellulaire dans l'espace et le temps, est fréquemment observée en biologie. Elle est nécessaire pour de nombreux mécanismes cellulaires essentiels allant de la division cellulaire et la migration au développement et la croissance polarisée. Comprendre comment la cellule génère et maintient cette polarité est crucial, les défauts de polarité étant liés à des maladies graves comme le cancer ou les maladies neurodégénératives. Chez la levure Saccharomyces cerevisiae, la polarité cellulaire est établie lorsque le module de la Rho GTPase Cdc42, qui comprend le facteur d'échange de nucléotide guanine (GEF) Cdc24 et la protéine scaffold Bem1, localise à un unique site à la membrane plasmique pour activer Cdc42 et ainsi, établir un axe de polarité utilisé pour la croissance et la division cellulaire. Les mécanismes responsables de l'activation de Cdc42 à un site unique au cortex pendant l'établissement de la polarité sont essentiels mais largement inconnus. En utilisant des expériences complémentaires d'imagerie in vivo et des expériences in vitro, je mis en évidence que le ciblage avide du module de Cdc42 à la membrane plasmique implique des interactions multivalentes entre des lipides anioniques et le module de Cdc42. En détail, j'ai démontré que la combinaison de plusieurs phospholipides anioniques, comprenant PS, PI4P et PI(4,5)P2, est nécessaire à la localisation de Bem1 et Cdc24 in vivo. J'ai identifié des groupements cationiques interagissant avec des lipides (CLICs) dans l'extrémité N-terminale de Bem1 qui étaient nécessaires et suffisants pour interagir avec des phospholipides anioniques. Réduire l’interaction de Bem1 avec les lipides en mutant la séquence CLICs a fortement diminué la localisation de Bem1 au niveau du cortex ainsi que la signalisation de Cdc42. En plus des CLICs de Bem1, le domaine PX de Bem1 et le domaine PH de Cdc24 augmentent davantage l'avidité du module GTPase pour les lipides anioniques et la combinaison des trois domaines est essentielle pour l'établissement de la polarité cellulaire. Ces résultats définissent pour la première fois le mécanisme de ciblage avide des activateurs de Cdc42 à la membrane plasmique pendant l'établissement de l'axe de polarité
Cell polarity, the asymmetric organization of cell material in space and time, is frequently observed in biology. It is required for numerous essential cellular processes ranging from cell division and migration to development and polarized growth. Addressing how cells generate and maintain polarity is crucial, since defects in polarity are linked to severe diseases including cancer and neurodegeneration. In the budding yeast Saccharomyces cerevisiae, cell polarity is established when the Cdc42 Rho GTPase module, which includes the Guanine nucleotide Exchange Factor (GEF) Cdc24 and the scaffold protein Bem1, accumulate at a unique site on the plasma membrane to activate Cdc42 and establish the polarity axis used for cell growth and division. The mechanisms responsible for the site-specific activation of Cdc42 at the cortex during polarity establishment are essential but are largely unknown. Using complementary in vivo imaging and in vitro experiments, I found that the avid targeting of the Cdc42 GTPase module to the plasma membrane involves multivalent anionic lipid-Cdc42 module interactions. I found that a combination of anionic phospholipids, including PS, PI4P and PI(4,5)P2, are necessary for Bem1 and Cdc24 localization in vivo. I identified Cationic-enriched Lipid Interacting Clusters (CLICs) in the N-terminus of Bem1 that were necessary and sufficient for anionic phospholipid interactions. Reducing Bem1 lipid binding by mutating the CLICs strongly diminished the localization of Bem1 at the cortex and Cdc42 signaling. In addition to the Bem1 CLICs, the Bem1 PX domain and the Cdc24 PH domain increased the avidity of the GTPase module for anionic lipids, and a combination of all three domains was essential for the establishment of cell polarity. The results of my thesis define a mechanism of avid targeting of Cdc42 activators to the cortex during polarity axis establishment
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Berggren, Anders. "LCA of Egg Phospholipids." Thesis, KTH, Industriell ekologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-134201.

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Egg phospholipids are a group of fats or lipids in the egg yolk, commonly used as emulsifiers in the chemical industry to facilitate the dissolving of substances. The pharmaceutical company Fresenius-Kabi manufactures this product and seeks a better understanding of the product’s major environmental impacts in order to comply with the ISO 14001 requirements, communicate its environmental performance and choose raw materials that result in lower environmental impacts. The aim of this study is to quantify and identify environmental impacts that occur in the life cycle of Fresenius-Kabi’s egg phospholipids product, and to suggest improvements on how the impacts could be reduced. The aim has been reached by following the life cycle assessment methodology. The life cycle consists of egg, egg yolk powder and egg phospholipids production. The major inputs to the life cycle include fertilizers, pesticides, hen feed, fuel oil and solvents. The major outputs are hen manure, egg residues, air and water emissions. The results show that the greatest impacts are generated in the production of hen feed, solvent feedstocks, the hen manure handing and the final egg phospholipids production. The most severe environmental impacts are found in the human toxicity and eutrophication impact categories. Pesticide and fertilizers usage in the cultivation of hen feed and solvent feedstocks generate phosphorus, manganese and arsenic emissions, which are emission substance sources in the human toxicity impact category. In addition, nitrate and phosphate emissions from fertilizer and hen manure affect the eutrophication. The emissions of NMVOC and carbon dioxide to air, as well as phosphorus to waste water, are the major environmental concerns in the final egg phospholipids manufacturing. Other impact categories such as climate change, photochemical oxidant formation, terrestrial acidification and fossil depletion have lower global impact. Five scenarios have been conducted in order to validate the results, and to provide Fresenius-Kabi with improvements. Lowering the production and intake of hen feed per kilogram eggs with six percent decrease the environmental impacts by 2 to 6 percent. Changing the ethanol feedstock to cellulose-based feedstocks clearly diminishes the toxicity related emissions due to lower fertilizer and pesticide usage. To replace other fat and protein sources with the egg residue byproduct that is yielded within the life cycle is the best treatment method of the egg’s non-phospholipids content. No specific improvements to the treatment method of the hen manure have been found. The fifth scenario includes a sensitivity analysis on the egg yolk powder allocation factor. To increase it from 11 to 25 percent does not give any significant effect on the final results, since this life cycle phase already has very low environmental impact. Actions that will have a significant effect on the egg phospholipids’ total environmental impact are optimize fertilizer and pesticide usage at hen feed and ethanol feedstock cultivations, lower ammonia and phosphate emissions from the hen manure management, and finally, reduced solvent, carbon dioxide, phosphorus and phosphate emissions from the final egg phospholipids manufacturing. Fresenius-Kabi is recommended to further look into these emission sources in order to decrease the egg phospholipids’ environmental impact.
Äggfosfolipider är ett fett eller lipider i äggulan som används som emulgator i kemiindustrin för att förenkla andra medels sammanlösning. Farmasiföretaget Fresenius-Kabi tillverkar den här produkten och söker bättre förståelse för de största miljöproblemen med produktionen av produkten i syfte att uppfylla krav inom ISO 14001, kommunicera sitt miljöarbete, och att välja råmaterial med låg miljöpåverkan. Målet med den här studien är att kvantifiera och identifiera de största miljöproblemen i ett livscykelperspektiv med produktionen av äggfosfolipid. Målet har uppnåtts genom att följa standardmetoden för livscykelanalyser. Livscykeln består av ägg-, äggule och äggfosfolipid produktion. Den mest signifikanta tillförseln av produkter är gödsel, pesticider, hönsavföring, eldningsolja och lösningsmedel. De mest signifikanta produkter som lämnar livscykeln är hönsgödsel, ägg rester, luft och vatten emissioner. Resultaten visar att de mest betydelsefulla miljöproblemen uppstår i äggfosfolipidens livscykel äggproduktionen av hönsfoder och råvaror för etanolproduktion, hanteringen av hönsgödsel och vid den slutgiltiga äggfosfolipid tillverkningen. De mest betydande miljöpåverkanskategorierna är utsläpp av för människan toxiska ämnen och övergödning.  Användandet av pesticider och gödsel vid produktion av råvaror till hönsfoder och etanol ger utsläpp av fosfor, mangan och arsenik, vilka är emissionskällor i den här kategorin. Emissioner av nitrat och fosfat från gödsel användning och hantering av hönsavföring är två emissionskällor till övergödningen. Miljöproblem som uppstår i den slutgiltiga äggfosfolipid produktionen är utsläpp av flyktiga kolväten vilka inte inkluderar metan, koldioxid och fosfor i avfallsvattnet. Andra påverkanskatergorier som till exempel klimatförändringarna, försurning och uttag av fossila bränslen har lägra global miljöpåverkan. Fem scenarioer har genomförts för att ge resultaten högre trovärdighet. Att minska produktion och intag av hönsfoder per kilogram ägg med sex procent minskar miljöpåverkan med 2 till 6 procent. Att byta råmaterial vid etanol produktionen till cellulosabaserade material minskar markant utsläppen av toxiska ämnen på grund av mindre användning av pesticider och gödsel. Att ersätta fett och protein källor med äggrester som uppstår i äggfosfolipidproduktionen ger mest nytta i ett miljöperspektiv. Ingen klar bästa behandlingsmetod för hönsavföringen har hittats. Femte scenariot inkluderar en känslighetsanalys på hur miljöpåverkan från äggulepulvret allokeras från övriga äggprodukter. Att öka allokeringsfaktor från 11 procent till 25 procent får ingen nämnvärd effekt på de totala resultaten, eftersom den livscykelfasen där äggulepulvret produceras redan har låg miljöpåverkan. Åtgärder som får störst påverkan på äggfosfolipidens totala miljöpåverkan är att optimera användandet av gödsel och pesticider vid fodertillverkningen och råvaruproduktion av etanol, minska utsläpp av ammonium och fosfater från hönsgödselavföring och gödselanvändning i samband med fodertillverkningen och råvaruproduktion av etanol samt lägre utsläpp av lösningsmedel, koldioxid, fosfor och fosfat från den slutgiltiga äggfosfolipidtillverkningen. Fresenius-Kabi rekomenderas att undersöka de här emissionskällorna för att minska miljöpåverkan från produktion av äggfosfolipid.
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7

Maheshwari, Sweta. "Caractérisation biochimique et cellulaire des enzymes clés du métabolisme des phospholipides chez Plasmodium falciparum." Thesis, Montpellier 2, 2012. http://www.theses.fr/2012MON20004.

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Le développement du parasite Plasmodium falciparum, responsable du paludisme, nécessite la synthèse de phospholipides et plus particulièrement de phosphatidylcholine (PC) et phosphaditylethanolamine (PE) qui représentent environ 85% de la totalité des phospholidipes du parasite. Leur synthèse s'effectue principalement par les voies métaboliques de novo, voies de Kennedy, en trois étapes enzymatiques. Les enzymes CTP: phosphoethanolamine cytidylyltransferase (ECT) et CTP: phosphocholine cytidylyltransferase (CCT) catalysent les étapes limitantes des deux voies de biosynthèse de la PE et de la PC, respectivement. Ces deux enzymes sont essentielles à la survie du parasite murin, P. berghei et représentent ainsi des cibles thérapeutiques potentielles. La PfCCT est constituée de deux domaines cytidylyltranférases (CT) répétés alors que l'enzyme homologue chez l'homme est composée d'un seul domaine. En revanche, pour la ECT, la présence de deux domaines CT est retrouvée chez toutes les espèces mais les analyses de séquences et de structures ont montré que des résidus importants du site catalytique liant le substrat n'étaient pas conservés dans le domaine CT C-terminal de la PfECT. Ce travail a eu pour but de déterminer les propriétés enzymatiques et les caractéristiques cellulaires de la PfECT et de la PfCCT. Les paramètres cinétiques de ces enzymes ont été quantifiés in vitro à l'aide protéines recombinantes ainsi que sur les enzymes endogènes à l'aide d'extraits parasitaires. Grâce à l'utilisation de protéines recombinantes ponctuellement mutées, nous avons montré que seul le domaine CT N-terminal de la PfECT est catalytiquement actif. Chez P. falciparum, la PfECT et la PfCCT sont exprimées tout au long du cycle intra-érythrocytaire du parasite. La PfECT est présente dans la fraction soluble du parasite alors que la PfCCT apparait aussi bien dans la fraction soluble qu'insoluble. Des expériences d'immunofluorescence ont montré que la PfECT est cytosolique. L'ensemble des résultats présentés apportent un éclairage important sur les fonctions et les propriétés de ces deux cibles potentielles et constituent les premières étapes indispensables à l'élaboration d'une approche thérapeutique
Phospholipids are essential for the growth and development of Plasmodium falciparum malaria parasite. Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) are its major structural phospholipids. This study focused on CTP: phosphoethanolamine cytidylyltransferase (ECT) and CTP: phosphocholine cytidylyltransferase (CCT) that catalyzes the rate-limiting steps of the de novo Kennedy pathways for PE and PC biosynthesis respectively. Both ECT and CCT are essential in the rodent malaria parasite P. berghei and constitute potential chemotherapeutic targets to fight against malaria. PfCCT consists of two very similar cytidylyltransferase (CT) domains whereas the human enzyme consists of only one CT domain. The presence of two CT domains in ECT seems to be widespread in all the organisms. Sequence and structural analysis showed that the C-terminal CT domain of ECT lacks key residues in the substrate binding motif. This study aimed at unravelling the enzymatic properties and cellular characteristics of PfECT and PfCCT enzymes. In addition, these studies addressed the key question if C-terminal CT domain of PfECT is catalytically active. Kinetic parameters of the enzymes were evaluated in vitro on native proteins as well as on recombinant proteins, the latter being produced in bacterial system. Cellular characterisation studies using polyclonal antisera showed that PfECT and PfCCT are expressed throughout the intra-erythrocytic life cycle of the parasite. PfECT is found mainly in soluble form in the parasite while PfCCT is present in soluble as well as insoluble forms in the parasite. Furthermore, immunofluorescence studies for PfECT revealed that it is mainly cytosolic. To assess the contribution of each CT domain to overall PfECT enzyme activity, recombinant PfECT mutants were generated by site-directed mutagenesis. Kinetic studies on these mutants indicated that the N-terminal CT domain was the only active domain of PfECT. Collectively, these results bring new insights into the kinetic and cellular properties of the enzymes and will pave the way in developing a future pharmacological approach
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8

Stewart, Laura. "Physical studies of diphytanylglycerol phospholipids." Thesis, University of Ottawa (Canada), 1988. http://hdl.handle.net/10393/5405.

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Cuccia, Louis A. "Biophysical properties of dimeric phospholipids." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0023/NQ29914.pdf.

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Mohan, Vijitha. "SELECTIVE ESTER CLEAVAGE IN PHOSPHOLIPIDS." MSSTATE, 2008. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07112008-141938/.

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Selective ester bond cleavage using lithium and zinc halides was attempted in a select group of phospholipids, namely phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylserine (PS). Several reaction parameters including catalyst (lithium chloride, lithium bromide, lithium iodide, zinc chloride, zinc bromide and zinc iodide), reaction temperature (21, 30, 50 and 60 oC), and reaction time (2 and 4 hours) were varied and the effects on cleavage studied. Reacted phospholipid samples were characterized by attenuated total reflectance (ATR) and transmission FTIR spectroscopy. The FTIR spectra of pure (unreacted) and reacted PC, PE and PE were analyzed qualitatively and quantitatively (Peak Height Ratio). The appearance of asymmetric carboxylate anion stretch (1577 cm-1) and symmetric phosphonyl dianion stretch (1006 cm-1) in the reacted phospholipid spectra reveals cleavage of ester bonds in carbonyl and phosphonyl. Reaction temperature and time did not significantly influence the cleavage results over the temperature and time range tested.
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Books on the topic "Phospholipids"

1

Hanin, Israel, and Giancarlo Pepeu, eds. Phospholipids. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0.

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Gregor, Cevc, ed. Phospholipids handbook. New York: Marcel Dekker, Inc., 1993.

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International Colloquium on Lecithin (5th 1989 Cannes, France). Phospholipids: Biochemical, pharmaceutical, and analytical considerations. New York: Plenum Press, 1991.

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Massarelli, Raphaël, Lloyd A. Horrocks, Julian N. Kanfer, and Konrad Löffelholz, eds. Phospholipids and Signal Transmission. Berlin, Heidelberg: Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-662-02922-0.

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1935-, Eichberg Joseph, ed. Phospholipids in nervous tissues. New York: Wiley, 1985.

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F, Kuo J., ed. Phospholipids and cellular regulation. Boca Raton, Fla: CRC Press, 1985.

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1943-, Massarelli Raphaël, North Atlantic Treaty Organization. Scientific Affairs Division., and NATO Advanced Research Workshop on Phospholipids and Signal Transmission (1991 : Wiesbaden, Germany), eds. Phospholipids and signal transmission. Berlin: Springer-Verlag, 1993.

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1933-, Kuo J. F., ed. Phospholipids and cellular regulation. Boca Raton, Fla: CRC Press, 1985.

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Ramadan, Mohamed Fawzy. Pheno-phospholipids and Lipo-phenolics. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-67399-4.

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H, Zeisel Steven, Szuhaj Bernard F, American Oil Chemists' Society, and International Congress on Phospholipids (7th : 1996 : Brussels, Belgium), eds. Choline, phospholipids, health, and disease. Champaign, Ill: AOCS Press, 1998.

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Book chapters on the topic "Phospholipids"

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Paltauf, F., and A. Hermetter. "Phospholipids — Natural, Semisynthetic, Synthetic." In Phospholipids, 1–12. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_1.

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Gregoriadis, Gregory. "Biological Behaviour of Liposomes." In Phospholipids, 123–32. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_10.

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Puisieux, F., G. Barratt, L. Roblot-Treupel, J. Delattre, P. Couvreur, and J. Ph Devissaguet. "Therapeutic Aspects of Liposomes." In Phospholipids, 133–65. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_11.

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Caderni, G. "The Effect of Phospholipids and Lipotropic Factors on Xenobiotic Toxicity." In Phospholipids, 167–76. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_12.

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Arndt, Dieter. "Phospholipids in Oncology." In Phospholipids, 177–83. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_13.

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Lachmann, Burkhard. "Phospholipids in Pulmonary Functions." In Phospholipids, 185–95. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_14.

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Feldheim, Walter. "Nutritional Aspects of Phospholipids and their Influence on Cholesterol." In Phospholipids, 197–204. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_15.

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Zubenko, George S. "Biological Markers of Alzheimer’s Disease: A View from the Perspective of Phospholipids in Membrane Function." In Phospholipids, 205–11. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_16.

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Nunzi, Maria Grazia, Fabrizio Milan, Diego Guidolin, Adriano Zanotti, and Gino Toffano. "Therapeutic Properties of Phosphatidylserine in the Aging Brain." In Phospholipids, 213–18. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_17.

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Zeisel, Steven H. "Phospholipids and Choline Deficiency." In Phospholipids, 219–31. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1364-0_18.

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Conference papers on the topic "Phospholipids"

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Bogojevic, Oliver, Carl Arevang, and Zheng Guo. "Synthesis of complex phospholipid species." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/rlyh7861.

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Phospholipids are essential for the preservation of life on the planet and carry numerous critical roles and functions, including being the main constituents of the cell-membranes in both eukaryotic and prokaryotic cells, providing (more bioavailable) energy, and maintaining chemical and electrical processes in the body. The structural characteristics of phospholipids can vary greatly among species, however, commonly consist of a hydrophilic region (phosphate-containing head-group) and a hydrophobic region (fatty acids, €œtails€), providing the amphiphilic features and unique functions. The countless number of possible configurations enables the continuous synthesis of novel phospholipid species. The synthesis of specific phospholipids, so-called €œdesigner-phospholipids€, is commonly carried out through modifications of more common and easily accessible phospholipid species, catalyzed by the use of either non-specific chemical catalysts or specific enzymes. Enzymatic methods, being most prominent, are often using biphasic reaction systems, allowing for the easy reuse of enzymes and separation of polar compounds, offering more environmentally friendly approaches'. The synthesis of complex phospholipids such as cardiolipins (CLs) and bis(mono/di-acylglycero)phopshates (BMPs/BDPs) have significant value as they carry the unique ability to contain multiple fatty acids, which in turn can be linked to a range of positive health effects. The positive health effects of fish oils (EPA/DHA) are today a hot topic, which in combination with complex phospholipids present great potential for future applications. Additionally, new phospholipid species are continuously under development utilizing completely new synthetic systems with environmentally friendly approaches' in focus. Modern methods centralized on the combinatorial use of ionic liquids and enzymes for the production of novel phospholipids species reduce the use of organic solvents, allowing for the incorporation of fatty acid esters of hydroxy fatty acids (FAHFAs) into phospholipids. The science behind the synthesis of phospholipids is continuously developing for an increased amount of different applications.
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Munch, Katharina, Claire Berton-Carabin, Karin Schroen, and Simeon Stoyanov. "Plant protein-stabilized emulsions: Implications of protein and non-protein components for lipid oxidation." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/zznf4565.

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The use of plant proteins to stabilize oil-in-water (O/W) emulsions has been an increasing trend lately. The complexity of the available plant protein ingredients, along with the proteins’ physicochemical properties, require advanced processing that typically leads to substantial concentrations of non-protein components in the final isolates or concentrates. It is known that those components, such as polyphenols, phytic acid or phospholipids, can have a strong influence on the oxidative stability of emulsions. Thus, to understand the oxidative stability of plant protein-stabilized emulsions, the influence of the non-protein components also needs to be considered. Many food emulsions, such as mayonnaise or infant formula, are stabilized by not only proteins, but also phospholipids. Such an interfacial protein-phospholipid combination can also be found in oleosomes, natural lipid droplets which show a high oxidative stability. This stability has been attributed to their interfacial architecture in which oleosins and phospholipids form a tight physical barrier against pro-oxidant species. However, while the antioxidant properties of proteins are widely reported, the contribution of phospholipids to lipid oxidation in plant protein-based emulsions remains underexplored. In this work, we investigated how mixed interfacial plant proteins and phospholipids may be rationally used to control the oxidative stability of O/W emulsions. The interfacial composition was modulated by varying the ratio between pea proteins and sunflower phosphatidylcholine (PC) while keeping the total concentration of pea proteins constant. Increasing the phospholipid-to-protein ratio led to a monotonic decrease in the concentration of proteins and an increase of phospholipids at the interface, while the oxidative stability of those O/W emulsions changed in a non-monotonic pattern. The results were put in perspective by embedding them in a context of reviewing the potential implications of typical components in plant protein ingredients on lipid oxidation.
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Dhara, Olivia, and Pradosh Chakrabarti. "Rice Bran Lyso-gums: The Unexplored Source of Potential Industrial Phospholipid." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/keww1142.

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Crude rice bran oil contains about 3-4% of phospholipids. In the conventional degumming process, these were removed from the oil by using water/acid degumming techniques. However, with the advent of enzymatic degumming technology, the conventional methods are no longer followed. Enzymatic degumming generates lyso-gums in contrast to the ordinary gums recovered by conventional degumming methods. Rice bran lyso gum contains primarily lyso-phosphatidyl choline (LPC). It also contains lyso phosphatidyl ethanolamine (LPE) phosphatidyl choline (PC), phosphatidyl inositol (PI), phosphatidyl ethanolamine (PE), etc, amongst other classes of phospholipids. Till date lyso-phospholipids are produced synthetically to meet their demand and abundant use. Natural alternatives can be of great importance and proper processing of the crude rice bran lyso-gum (CRBLG) will definitely produce various modified lyso-gums having specific industrial applications in cosmetics, paint, and leather industries. The present work focuses on the processing of crude RBLG to produce various lyso-phospholipids products. Initially, bleaching of CRBLG was carried out using various oxidative bleaching agents such as hydrogen peroxide, benzoyl peroxide, and sodium chlorite. Bleached lyso-lecithin with a reduction in color from 18+ to 16 Gardner Units was obtained under optimized conditions. Processes were also developed to produce LPC enriched rice bran lyso-phospholipids as well as acetylated lysophospholipids. Acetylated RBL was obtained by enzymatic modification. The phospholipid compositions of these modified rice bran lyso-lecithins were estimated by using 31P NMR and surfactant properties were also checked for some of these modified products. Lyso-PC enrichment of about 40-50% could be achieved. Emulsion stability was significantly improved for LPC enriched products. The basic raw materials are available in bulk quantities and have less price. It is, therefore, expected that the modified lyso-lecithin products can be produced in an economically feasible method to meet the demand of various industries.
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Pengo, V., M. J. Heine, P. Thiagarajan, and s. s. Shapiro. "A GENERAL MECHANISM FOR LUPUS ANTICOAGULANTS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643660.

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Although- a number of observations have implied that lupus anticoagulants have immunologic specificity towards anionic. phospholipids, thereby prolonging phospholipid-dependent coagulation tests, this assumption has been directly demonstrated in only one patient with a monoclonal IgM paraprotein. We have tested the generality of this hypothesis directly by isolating five IgG lupus anticoagulants from patients with lupus-like syndromes and/or thrombosis. IgG lupus anticoagulant fractions were isolated free of other plasma proteins and free of contaminating phospholipid by adsorption to and elution from cardiolipin-cholesterol-dicetylphosphate liposomes , followed by chromatography on protein A-Sepharose. Cardiolipin liposomes, but not phosphatidylcholine liposomes, were capable of removing all, or nearly all, lupus anticoagulant activity from patient plasma. Anticardiolipin and lupus anticoagulant activity were both present in acidic fractions on isoelectric focusing. F(ab’)2 fragments retained lupus anti coagulant activity and bound to cardiolipin in an ELISA assay. The affinity-purified IgG preparations reacted with cardiolipin, phosphatidyl serine , phosphatidylinositol and phosphatidic acid, but not with phosphatidylcholine or phosphatidyl ethanol amine, and inhibited calcium-dependent binding of prothrombin and of factor X to phosphatidy1serine-coated surfaces. These data demonstrate a general mechanism for the action of lupus anticoagulants: antibodies that have immunologic specificity towards anionic phospholipids, thereby blocking the calcium-mediated binding of vitamin K-dependent coagulation factors to coagulation-active phospholipid surfaces.
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Lambers, J. W. J., M. Cammenga, B. Konig, H. Pannekoek, and J. A. van Mourik. "ACTIVATION OF HUMAN ENDOTHELIAL TYPE PLASMINOGEN ACTIVATOR INHIBITOR (PAI-1) BY NEGATIVELY CHARGED PHOSPHOLIPIDS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1642807.

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The endothelial cell type plasminogen activator inhibitor (PAI-1) may exist in an active, latent form that can be converted into an active form upon exposure to denaturants such as sodium dodecyl sulphate (SDS), guanidine-HCl or urea. Here we show that latent PAI-1 can be activated with lipid vesicles, consisting of the negatively charged phospholipids phosphatidylserine (PS) or phosphatidylinositol (PI). The presence of a net negative charge on the phospholipid headgroup is essential for activation. Incubation with lipid vesicles, consisting of the zwitterionic phospholipids phosphatidylcholine (PC) and phosphatidylethanol-amine (PE), does not result in activation of the inhibitor. In the presence of PS vesicles, the capacity of PAI-1 to inhibit tissue type plasminogen activator (t-PA) is 50-fold higher than that of the untreated protein. For comparison, the activity of PAI-1 was enhanced 25-fold by treatment of the protein with SDS. PS induces activation of the inhibitor at much lower concentrations than SDS. For example, to achieve 50% inhibition of t-PA with a more than 100-fold excess of PAI-1, 0.25 nmoles of PS are required, whereas L.60 nmoles of SDS are necessary to reach half maximal inactivation of t-PA. Activation of PAI-1 by PS can be reversed by the addition of Ca2+-ions, suggesting that Ca2+-ions interfere with the interaction of PAI-1 with the negatively charged lipid surface, thus preventing its activation. The lipid-induced activation of PAI-1 points to a possibly important role of phospholipids in fibrinolysis; regulation of the fibrinolytic activity in blood plasma may ultimately be determined by the extent to which these phospholipids activate the inhibitor of t-PA.This study was supported by the Netherlands Thrombosis Foundation.
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Schroeder, Avi, Gabi Verberne, Yulia Merkher, Dvorah Diminsky, Alice Maroudas, Gregory Halperin, Dorrit Nitzan, Izhak Etsion, Yechezkel Barenholz, and Sarit Sivan. "Surface Active Phospholipids as Cartilage Lubricants." In ASME 2008 9th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2008. http://dx.doi.org/10.1115/esda2008-59523.

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Efficient lubrication and extremely low friction are essential for proper functioning of synovial joints. Various joint dysfunctions were described in direct association with increased friction or adhesive forces. Surface-active phospholipids (SAPLs) are well known to reduce friction in synovial joints. This study demonstrates, using a novel human-sourced cartilage-on-cartilage setup, the potential of multilamellar vesicles (MLV) composed of the SAPL dimyristoyl phosphatidylcholine (DMPC) to act as effective lubricants, reducing static and dynamic friction-coefficients to levels of healthy synovial joints. Furthermore, MLV composed of DMPC, in sizes ranging from 0.8 to ∼3.5 μm, were found to be more effective lubricants than histidine buffer, saline, or synovial fluid. The ability to test new cartilage lubricants, simulating, to a great extent, natural conditions, using the setup presented herein is discussed.
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Rosing, J., H. Speijer, J. W. P. Govers-Riemslag, and R. F. A. Zwaal. "THE EFFECT OF PROCOAGULANT PHOSPHOLIPID VESICLES WITH NET POSITIVE CHARGE ON THE ACTIVITY OF PROTHROMBINASE." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643839.

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It is generally thought that procoagulant phospholipid surfaces that promote the activation of vitamin K-dependent coagulation factors should have a net negative charge in order to promote calcium-dependent binding of the enzymes (FVIIa, FIXa and FXa) and substrates (prothrombin and FX) of the coagulation factor-activating complexes. Two models have been proposed to explain calcium-mediated association of vitamin K-dependent proteins with phospholipid: a) an electrostatic model, in which a positively-charged protein-calcium complex is attracted by a negatively-charged phospholipid surface and b) a chelation model in which a coordination complex is formed between calcium ions, γ-carboxyglutamic acids of the proteins and negatively-charged membrane phospholipids. To study the effect of the electrostatic potential of phospholipid vesicles on their activity in the pro-thrombinase complex the net charge of vesicles was varied by introduction of varying amounts of positively-charged stearylamine in the membrane surface. Introduction of 0-15 mole% stearylamine in phospholipid vesicles that contained 5 mole% phosphatidylseri-ne (PS) hardly affected their activity in prothrombin activation. Electrophoretic analysis showed that vesicles with > 5 mole% stearylamine had a net positive charge. The procoagulant activity of vesicles that contained phosphatidic acid, phosphatidylglyce-rol, phosphatidylinositol or phosphatidyl-glactate (PLac) as acidic phospholipid was much more effected by incorporation of stearylamine. Amounts of stearylamine that compensated the negative charge of acidic phospholipid caused considerable inhibition of the activity of the latter vesicles in prothrombin activation. The comparison of vesicles containing PS and PLac as acidic phospholipid is of special interest. PS and PLac only differ by the presence of NH+ 3-group in the serine moiety of PS. Thus, in spite of the fact that vesicles with PLac are more negatively charged than vesicles with PS, they are less procoagulant. Our results show that a) although procoagulant membranes have to contain acidic phospholipids there is no requirement for a net negative charge, b) the amino group of phosphatidylserine has an important function in the interaction of procoagulant membranes with vitamin K-dependent proteins and c) the chelation model can satisfactorily explain calcium-mediated lipid-protein association.
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Purdon, A. D., and J. B. Smith. "RELEASE AND TRANSACYLATION OF ARACHIDONATE FROM A COMMON POOL OF 1-ACYL-2-ARACHIDONOYL GLYCEROPHOSPHOCHOLINE IN HUMAN PLATELETS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643391.

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We have previously shown that the main source of arachidonate in thrombin-stimulated human platelets is 1-acyl-2-arachidonoyl (AA) glycerophosphocholine (GPC) and release of 3H-AA from this phospholipid also was correlated with increased 3H-AA in ether phospholipid. This ATP independent transfer of 3H-AA from 1,2 diacyl GPC to ether phospholipid (transacylation) also occurs in resting cells. Human platelets in 1/10 volume of plasma (ACD anticoagulant, pH 6.5) were radiolabelled with 3H-AA for 60 min at 37°C and then exogenous 3H-AA was removed by gel filtration into Tyrode's buffer, pH 7.4, 0.2% albumin. These radiolabelled cells were incubated in the absence of exogenous 3H-AA for four hours followed by Bligh and Dyer extraction and thin layer chromatography purification of phospholipids. 3H-AA in 1,2 diacyl GPC was found to decrease by over 20% and increase substantially in 1-0-alkyl-2-acyl GPC and 1-0-alk-1'-enyl-2-acyl glycerophospho ethanolamine (GPE), In this same time interval the mass of AA released by thrombin (5 U/ml, 10 min, 37°C, no stirring)in the presence of BIT 775C and measured by GLC, stayed the same (30 nmoles/109 cells), however, the specific activity decreased. Using reverse phase HPLC to resolve diradylglycerobenzoate derivatives of phospholipids: acylation, deacylation, and transacylation were observed for individual AA-containing molecular species of phospholipid, including those with an unsaturated fatty acid at sn-1. In particular the radiolabellinq of the 1-unsaturate-2-arachidonoyl GPC correlated with the specific activity of the 3H-AA released by stimulation with thrombin. Furthermore, 1-arachidonoyl-2-3H-arachidonoyl GPC was completely deacylated while 50 % of its mass remained. This contrasted with 16:0, and 18:0-2-arachidonoyl GPC in which the specific activity remained the same before and after deacylation. We conclude that deacylation of AA-containing molecular species of 1,2 diacyl GPC in stimulated cells includes molecular species which are also a source of arachidonic acid for transacylation reactions.
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Reynaud, J. A., A. Brack, J. P. Grivet, and Y. Trudelle. "Interaction of phospholipids with basic amphiphilic polypeptides." In The living cell in four dimensions. AIP, 1991. http://dx.doi.org/10.1063/1.40574.

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Rathnakumar, Kaavya, and Sergio Martinez-Monteagudo. "Extraction of dairy phospholipids using switchable solvents." In Virtual 2021 AOCS Annual Meeting & Expo. American Oil Chemists’ Society (AOCS), 2021. http://dx.doi.org/10.21748/am21.575.

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Reports on the topic "Phospholipids"

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Miller, Duane D. Selective Cytotoxic Phospholipids for Prostate Cancer. Fort Belvoir, VA: Defense Technical Information Center, October 2005. http://dx.doi.org/10.21236/ada447581.

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Miller, Duane D. Selective Cytotoxic Phospholipids for Prostate Cancer. Fort Belvoir, VA: Defense Technical Information Center, October 2002. http://dx.doi.org/10.21236/ada412138.

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Liangpunsakul, Suthat. Phospholipids as Biomarkers for Excessive Alcohol Use. Fort Belvoir, VA: Defense Technical Information Center, October 2014. http://dx.doi.org/10.21236/ada613998.

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Hong, Mei. Two-dimensional NMR investigations of the dynamic conformations of phospholipids and liquid crystals. Office of Scientific and Technical Information (OSTI), May 1996. http://dx.doi.org/10.2172/6429.

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Dospatliev, Lilko. Macro and Micro Elements, Phospholipids and Fatty Acids in Edible Wild Mushroom (Cantharellus cibarius) from Batak Area (Rhodope Mountains, Bulgaria). "Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences, November 2018. http://dx.doi.org/10.7546/crabs.2018.11.03.

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Kelly, Karen, and Rene Jacobs. Phospholipid Biosynthesis. AOCS, July 2011. http://dx.doi.org/10.21748/lipidlibrary.39191.

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Montville, Thomas J., and Roni Shapira. Molecular Engineering of Pediocin A to Establish Structure/Function Relationships for Mechanistic Control of Foodborne Pathogens. United States Department of Agriculture, August 1993. http://dx.doi.org/10.32747/1993.7568088.bard.

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This project relates the structure of the bacteriocin molecule (which is genetically determined) to its antimicrobial function. We have sequenced the 19,542 bp pediocin plasmid pMD136 and developed a genetic transfer system for pediococci. The pediocin A operon is complex, containing putative structural, immunity, processing, and transport genes. The deduced sequence of the pediocin A molecule contains 44 amino acids and has a predicted PI of 9.45. Mechanistic studies compared the interaction of pediocin PA-1 and nisin with Listeria monocytgenes cells and model lipid systems. While significant nisin-induced intracellular ATP depletion is caused by efflux, pediocin-induced depletion is caused exclusively by hydrolysis. Liposomes derived from L. monocytogenes phospholipids were used to study the physical chemistry of pediocin and nisin interactions with lipids. Their different pH optima are the results of different specific ionizable amino acids. We generated a predicted 3-D structural model for pediocin PA-1 and used a variety of mutant pediocins to demonstrate that the "positive patch" at residues 11 and 12 (and not the YGNGV consensus sequence) is responsible for the binding step of pediocin action. This structure/function understanding gained here provides necessary prerequisites to the more efficacious use of bacteriocins to control foodborne pathogens.
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Granick, Steve. Phospholipid Vesicles in Materials Science. Office of Scientific and Technical Information (OSTI), May 2016. http://dx.doi.org/10.2172/1252427.

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Boss, W. Cell signalling and phospholipid metabolism. Office of Scientific and Technical Information (OSTI), January 1989. http://dx.doi.org/10.2172/5943691.

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Boss, W. F. Cell signalling and phospholipid metabolism. Office of Scientific and Technical Information (OSTI), January 1990. http://dx.doi.org/10.2172/7045128.

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