see also Model lipidbilayer The lipidbilayer is a thin membrane made of two layers of lipid molecule ... membrane of almost all life living organisms and many virus es are made of a lipidbilayer, as are the membranes surrounding the cell nucleus and other sub cellular structures. The lipidbilayer ... transporter ion pumps . Image Lipidbilayer section.gif right thumb 300px This fluid lipidbilayer .... Structure and organization A lipidbilayer, also known as the phospholipid bilayer, is a sheet ... interaction between the hydrophobic lipid tails and the surrounding water. Thus, a lipidbilayer ... interference effects cause rainbow colors on a bubble surface. A single lipidbilayer, on the other ... left thumb 310px Schematic cross sectional profile of a typical lipidbilayer. There are three distinct ... region with partial hydration Cross section analysis The lipidbilayer is very thin compared to its ... of a watermelon 1 ft 30 cm , the lipidbilayer making up the plasma membrane would be about ... , ref name Lewis1983 cite journal author Lewis BA, Engelman DM title Lipidbilayer thickness .... ref name Trauble1971 cite journal author Trauble H, Haynes DH title The volume change in lipidbilayer ... Asymmetrical lipidbilayer structure for biological membranes journal Nature volume 236 issue 61 pages .... further2 Lipidbilayer phase behavior At a given temperature a lipidbilayer can exist in either a liquid ... across the bilayer, but in liquid phase bilayers a given lipid will exchange locations with its neighbor ... phase bilayer are locked in place. The phase behavior of lipid bilayers is largely determined by the strength ... of an organism or of life. This barrier takes the form of a lipidbilayer in all known life ... pmid 6242168 doi 10.1007 BF02102359 ref The partitioning ability of the lipidbilayer is based on the fact ... across the bilayer below. Prokaryote s have only one lipidbilayer the cell membrane also ... bilayer. Signaling see also Neurotransmission Lipid raft Probably the most familiar form ... more details
A model lipidbilayer is any bilayer assembled in vitro , as opposed to the bilayer of natural cell membrane ... membranes BLM Image Black lipid membrane.svg right thumb 350px Schematic of a painted bilayer experiment ... bilayer system developed was the painted bilayer, also known as a black lipid membrane. The term painted ... planar lipidbilayer membranes. Biophysical Journal . 12. 1972 432 445. ref The term black bilayer ... used in conjunction with painted lipid bilayers. Simple measurements indicate when a bilayer forms ... Planar LipidBilayer Membranes Anchored to an In Situ Polymerized Hydrogel. Advanced Materials. 20 ... lipid bilayers SLB Image Supported bilayer.svg right thumb 290px Diagram of a supported bilayer Unlike a vesicle or a cell membrane in which the lipidbilayer is rolled into an enclosed shell ... to the study of lipid bilayers. One of the greatest advantages of the supported bilayer is its stability ... black lipid membranes, the presence of holes will not destroy the entire bilayer. Because of this stability ..., and M Tanaka. Deposition of highly resistive lipidbilayer on silicon silicon dioxide electrode .... Atomic force microscopy AFM has been used to image lipidLipidbilayer phase behavior phase .... More recently, AFM has also been used to directly probe the Lipidbilayer mechanics mechanical properties ... to study of supported lipidbilayer formation kinetics Anal. Chem., 80 10 , 3666 3676 2008 ... Lowery, A P Wong, and J T Groves. Nonequilibrium Adhesion Patterns at LipidBilayer Junctions. Journal ..., and E Sackmann. Lipid mono and bilayer supported on polymer films Composite polymer lipid films ... Research in this area is ongoing. Tethered BilayerLipid Membranes t BLM The use of a tethered bilayerlipid membrane t BLM further increases the stability of supported membranes by chemically ... G, Osman P, et al title Tethered bilayerlipid membranes as a support for membrane active peptides ... showing a solution of molecules green dots trapped in the vesicle interior. A vesicle is a lipidbilayer ... more details
merge Lipid polymorphism date February 2012 One of the most important properties of a lipidbilayer is the relative mobility fluidity of the individual lipid molecules and how this mobility changes with temperature. This response is known as the phase behavior of the bilayer. Broadly, at a given temperature a lipidbilayer can exist in either a liquid or a solid phase. The solid phase is commonly referred ... this plane. Thus, in a liquid bilayer a given lipid will rapidly exchange locations with its neighbor ... mobility, it is very difficult for lipid molecules to flip flop from one side of the bilayer to the other. In a phosphatidylcholine based bilayer this process typically occurs over a timescale of weeks ... This discrepancy can be understood in terms of the basic structure of the bilayer. For a lipid to flip from one leaflet to the other, its hydrated headgroup must cross the hydrophobic core of the bilayer .... The presence of cholesterol exerts a profound but complicated influence on lipidbilayer .... Elastic deformation and failure of lipidbilayer membranes containing cholesterol. Biophysical ... between cholesterol and lipids in bilayer membranes Role of lipid headgroup and hydrocarbon chain ... the Lipidbilayer mechanics mechanical rigidity of fluid bilayers ref name Boal2002 D. Boal ... 377 388. ref References reflist DEFAULTSORT LipidBilayer Phase Behavior Category Membrane biology ... melt from the gel to liquid phase. In both phases the lipid molecules are constrained to the two ... bilayer are locked in place and exhibit neither flip flop nor lateral mobility. Due to this limited ... composed of fluid phase bilayers. Physical Origins Image Lipid unsaturation effect.svg right thumb 320px Diagram showing the effect of unsaturated lipids on a bilayer. The lipids with an unsaturated tail blue disrupt the packing of those with only saturated tails black . The resulting bilayer has ... behavior of lipid bilayers is largely determined by the strength of the attractive van der Waals force ... more details
Orphan date April 2012 Lipidbilayer characterization is the use of various optical, chemical and physical probing methods to study the properties of lipid bilayers. Many of these techniques are elaborate and require expensive equipment because the fundamental nature of the lipidbilayer makes it a very difficult structure to study. An individual bilayer, since it is only a few nanometers thick, is invisible in traditional light microscopy. The bilayer is also a relatively fragile structure since ... phase lipidbilayer membranes. Biophysical Journal. 60. 1991 1553 1554. ref While correct, this distinction ... than a typical cell but much larger than the thickness of a lipidbilayer. More recently, advanced ... when two bilayers Lipidbilayer fusion fuse and their components mix. ref name Guohua2003 L. Guohua and R. C. Macdonald. Lipidbilayer vesicle fusion Intermediates captured by high speed microfluorescence ... LipidBilayer Biophysical Journal. 80. 2001 1829 1836. ref The sensitivity of this system is such that even ... the solvent lipid plug thins down to a single bilayer. Optical Lipids are highly polar molecule s which ... to study of supported lipidbilayer formation kinetics Anal. Chem., 80 10 , 3666 3676 2008 ref ... AFM scan of a supported lipidbilayer. The pits are defects in the bilayer, exposing the smooth surface ... the lipidbilayer formation and 2 to observe adsorption of single insulin molecules onto exposed ... individual lipid molecules, which has led to its use in characterizing Lipidbilayer phase behavior ... resistance which measured bilayer properties but did not actually image the bilayer. Later, protocols were developed to modify the bilayer and allow its direct visualization at first in the electron ... recently, dual polarisation interferometry has been used to measure the optical birefringence of lipid ... necessary to include a dye molecule in order to study lipid bilayers with fluorescence microscopy ..., some combination of the two. The dye is usually attached either to a lipid or a molecule that closely ... more details
Lipidbilayer mechanics is the study of the physical material properties of lipid bilayers , classifying bilayer behavior with stress mechanics stress and strain materials science strain rather than biochemical ... Forces. 2nd ed. 2002 Academic Press. ref To calculate K sub a sub for a bilayer it is necessary to multiply the monolayer value by two, since a bilayer is composed of two monolayer leaflets. Based on this calculation, the estimate of K sub a sub for a lipidbilayer should be 80 200 mN m note ... govern whether a lipid will form a bilayer or not solubility and shape. For a self assembled structure such as a bilayer to form, the lipid should have a low solubility in water, which can also be described .... 1996 135 160. ref References reflist DEFAULTSORT LipidBilayer Mechanics Category Biotechnology Category ... of K sub a sub and K sub b sub affect the ability of proteins and small molecules to insert into the bilayer ... 155. ref ref name McIntosh2006 T. J. McIntosh and S. A. Simon. Roles of Bilayer Material Properties ... 198. ref Bilayer mechanical properties have also been shown to alter the function of mechanically activated ..., F. Sachs and P. A. Gottlieb. Bilayer dependent inhibition of mechanosensitive channels by neuroactive ... membranes see also Elastic Modulus Since lipid bilayers are essentially a two dimensional structure ... would vary linearly with bilayer thickness as it would for a thin plate of isotropic material. In fact this is not the case and K sub a sub is only weakly dependent on bilayer thickness. The reason for this is that the lipids in a fluid bilayer rearrange easily so, unlike a bulk material ... in a bilayer is a result of the extra hydrophobic area exposed to water upon pulling the lipids ... is 2 , where gamma is the surface tension of the water lipid interface. Typically gamma is in the range ... of lipid bilayers. Biophysical Journal . 79. 2000 328 39. ref The compression modulus is difficult ... microscopy AFM has been used to probe the mechanical properties of suspended bilayer membranes, ref ... more details
Image Lipidbilayer fusion.svg right thumb 300px Illustration of lipid vesicles fusing showing two possible outcomes hemifusion and full fusion. In hemifusion only the outer bilayer leaflets mix. In full ... sub divided by lipidbilayer membranes. Exocytosis , fertilization of an egg biology egg by sperm ... into the host cell enveloped viruses are those surrounded by a lipidbilayer some others have only ... results from the Lipidbilayer mechanics energetically active edges formed during electroporation ... fusion References reflist DEFAULTSORT LipidBilayer Fusion Category Membrane biology Category Biophysics ... distinct lipid bilayers merge their hydrophobic cores, resulting in one interconnected structure ... from each bilayer is involved in the fusion process, the bilayers are said to be hemifused. In hemifusion, the lipid constituents of the outer leaflet of the two bilayers can mix, but the inner leaflets remain distinct. The aqueous contents enclosed by each bilayer also remain separated. Fusion is involved ... by fusion, as many bilayer coated viruses have dedicated fusion proteins to gain entry into the host cell. Lipid mechanism further2 Interbilayer forces in membrane fusion There are four fundamental steps ... more definitive study, many experiments have been performed in vitro with synthetic lipid vesicles ... of the bilayer, diminishing electrostatic repulsion and allowing the membranes to approach each ... fusion and lipid lateral segregation in phosphatidylcholine phosphatidic acid vesicles. Biochemistry ... to water. The resulting displacement of calcium for water destabilizes the lipid water interface ... of Phosphatidylserine Vesicles and the Role of Bilayer Curvature. Biochemistry. 20. 1981 3126 3133 ... The role of lipid headgroup in the fusion process extends beyond charge density and can affect dehydration ... phosphatidylethanolamine PE increases fusion when incorporated into a phosphatidylcholine bilayer .... Protein lipid interplay in fusion and fission of biological membranes. Annual Reviews of Biochemistry ... more details
Unreferenced stub auto yes date December 2009 For bilayers in biology, see lipidbilayer A bilayer is a double layer of closely packed atoms or molecules. The properties of bilayers are studied in condensed matter physics , often in the context of semiconductor device s, where two distinct materials are united to form junction physics junction s such as p n junction s, Schottky junction s, ... . See also Monolayer Inorganic nanotube Nanotube Semiconductor Thin film Category Phases of matter Category Thin films Condensedmatter stub ru ... more details
s, are ubiquitous in nature and are key components of the lipidbilayer of cells, ref name ... , a micelle , and a lipidbilayer . A biological membrane is a form of lipidbilayer . The formation ... membrane s, and as important lipid signaling signaling molecules . ref name pmid19098281 cite journal ... M and Dennis E.A title Update of the LIPID MAPS comprehensive classification system for lipids journal Journal of Lipid Research volume 50 pages S9 S14 year 2009 pmid 19098281 doi 10.1194 jlr.R800095 ... . ref name pmid19098281 Although the term lipid is sometimes used as a synonym for fat s, fats are a subgroup ... part of a lipid, are a diverse group of molecules synthesized by chain elongation of an acetyl ... Brown cite book editor Brown HA title Lipodomics and Bioactive Lipids Mass Spectrometry Based Lipid ... to sight. ref name The Lipid Chronicles cite web title A Long Lipid, a Long Name Docosahexaenoic Acid url http www.samuelfurse.com 2011 12 a long name a long lipid docosahexaenoic acid work The Lipid Chronicles accessdate 2011 12 31 ref Other major lipid classes in the fatty acid category are the fatty ... synthesis and their regulation journal Progress in Lipid Research volume 43 pages 134 76 ... journal Progress in Lipid Research volume 46 issue 5 pages 225 43 year 2007 pmid 17599463 doi 10.1016 ... 2011 11 the structure of a membrane work The Lipid Chronicles accessdate 2011 12 31 ref as well as being ... in lower animals journal Prog. Lipid Res volume 32 issue 1 pages 25 45 year 1993 pmid 8415797 doi ... E, Danikiewicz W title Polyisoprenoids structure, biosynthesis and function journal Progress in Lipid ... thumb right 300px Structure of the saccharolipid Kdo sub 2 sub Lipid A. ref name Raetz2006 ... of the lipid A Lipid A component of the lipopolysaccharide s in Gram negative bacteria . Typical ... is Kdo sub 2 sub Lipid A, a hexa acylated disaccharide of glucosamine that is glycosylated with two ..., Deems RA, Dennis EA title Kdo2 Lipid A of Escherichia coli , a defined endotoxin that activates macrophages ... more details
Image Lipid A.png thumb 250px Chemical structure of lipid A as found in E. Coli ref name Raetz2009 cite journal author Raetz, Christian R. H. Guan, Ziqiang Ingram, Brian O. Six, David A. Song, Feng Wang, Xiaoyuan Zhao, Jinshi title Discovery of new biosynthetic pathways the lipid A story journal Journal of Lipid Research year 2009 pages S103 S108 ref Lipid A is a lipid component of an endotoxin held responsible for toxicity of Gram negative bacteria . It is the innermost of the three regions of the lipopolysaccharide ... its toxic effects can be damaging, the sensing of lipid A by the human immune system may also be critical ... VK, Carlson RW, Stephens DS title Endotoxin of Neisseria meningitidis composed only of intact lipid ... activating abilities of LPS can be attributed to the lipid A unit. It is a very potent stimulant ... composition Lipid A consists of two glucosamine carbohydrate sugar units with attached acyl chains ... The optimal immune activating lipid A structure is believed to contain 6 acyl chains. Four acyl .... E. coli lipid A, as an example, typically has four C14 hydroxy acyl chains attached to the sugars ... for Lipid A in E. coli has been determined by the work of Christian R. H. Raetz in the past 32 years. ref name Raetz Lipid A structure and effects on eukaryotic cells have been determined and examined ... center thumb 700px Synthesis of the UDP diacylglucosamine precursor of Lipid A ref name King cite ... of Lipid IV sub a sub ref name King Inhibition and activation of immune response Lipid A with a reduced ... versions of lipid A can be used as components of vaccine s adjuvant s to improve their effect. Citation needed date March 2009 Mechanism of activating cells Lipid A and LPS has been demonstrated ... al., Nature 2009 . Consequently, lipid A Structural analog analogs like eritoran can act as TLR4 receptor ... Medicine ref See also Lipid A deacylase PagL References reflist External links MeshName Lipid A http www.lipidlibrary.co.uk Lipids lipidA index.htm The Lipid Library Summary of Lipid A and bacterial ... more details
physics stub Bilayer graphene BLG Citation needed date July 2011 is a material consisting of two layers of Graphene that are sometimes separated by a dielectric . Citation needed date July 2011 Quantum Hall Effect Like a single layer of Graphene, BLG has been shown to exhibit the Graphene Anomalous quantum Hall effect quantum hall effect . Excitonic Condensation Bilayer graphene is being studied for its potential to realize a Bose Einstein condensate of Exciton excitons . ref name PRL104.096802 Cite doi 10.1103 PhysRevLett.104.096802 ref Electron Electrons and Electron hole holes are fermions , but when they form an exciton, they become bosons allowing for the Bose Einstein condensate to occur. An exciton condensate in a bilayer system has been shown theoretically to carry a large Electric current current . ref name nphys1055 Cite doi 10.1038 nphys1055 ref Bilayer Graphene FETs BLG can be used to construct Field effect transistor field effect transistors ref name NatureNano2010.89 Cite doi 10.1038 nnano.2010.89 ref Reflist Category Carbon forms Category Emerging technologies Category Nanomaterials Category Semiconductor materials ... more details
Context date May 2009 Lipid microdomains are formed when lipid s undergo lateral phase matter phase separations yielding stable coexisting lamellar Lipidbilayer domain s. These phase separation s can be induced by changes in temperature , pressure , ionic strength or by the addition of divalent cation s or protein s. The question of whether such lipid microdomains observed in model lipid systems also exist in biomembrane s had motivated considerable research efforts. Lipid domains are not readily isolated and examined as unique species, in contrast to the examples of lateral heterogeneity . One can disrupt the membrane and demonstrate a heterogeneous range of wikt composition composition in the population of the resulting Vesicle biology vesicles or fragment s. Electron microscopy can also be used to demonstrate lateral inhomogeneities in biomembranes. Often, lateral heterogeneity has been inferred from biophysical techniques where the obsereved signal indicates multiple populations rather ... coefficient of a fluorescent lipid analogue in soybean protoplast s. Membrane microheterogeneity is sometimes ... with the average lipid physical state exhibited by the bulk of the membrane. Often, the methods suggest regions with different lipid fluidity , as would be expected of coexisting gel and liquid ... and gel like domains. See also Commons category Lipids Biochemistry Essential fatty acid Lipid ... B. Gennis, p. 164, Springer Verlag, New York, 1989. Shape instabilities in charged lipid domains.Journal ... Carboxyl Terminal Domains on Lipid Raft Localization of the Murine Gonadotropin Releasing Hormone Receptor. Biology of Reproduction 74 5 788 797. 2006. Investigation of the lipid domains and apolipoprotein ... cgi content abstract 94 8 3104 Lipid microdomain formation. http www.jimmunol.org cgi reprint 168 6 2737.pdf Lipid microdomain clustering. http medcat.wustl.edu catflat BME B720468.html Lipid microdomain signaling. DEFAULTSORT Lipid Microdomain Category Biochemistry ... more details
merge Lipidbilayer phase behavior date February 2012 Image Phospholipids aqueous solution structures.svg thumb Cross Section view of the structures that can be formed by phospholipids in aqueous solutions Polymorphism in biophysics is the aspect of the behaviour of lipid s that influences their long range order, i.e. how they aggregate. This can be in the form of spheres of lipid molecules micelle s , pairs of layers that face one another lamellar phase, observed in biological system as a lipidbilayer , a tubular arrangement hexagonal crystal system hexagonal , or various cubic crystal system cubic phases Fd3m, Im3m, Ia3m, Pn3m, and Pm3m being those discovered so far . More complicated aggregations have also been observed, rhombohedral , tetragonal and orthorhombic phases have been observed. It forms an important part of current academic research in the fields of membrane biophysics polymorphism , biochemistry biological impact and organic chemistry synthesis . Determination of the topology of a lipid system is possible by a number of methods, the most reliable of which is x ray diffraction . This uses a beam of x rays that are scattered by the sample, giving a diffraction pattern ..., temperature, hydration, pressure and ionic strength and type . Hexagonal phases in the lipid polymorphism In lipid polymorphism, if the packing ratio of lipids is greater or less than one, lipid ... form according to the environment the lipid is introduced. Hexagonal I phase H sub I sub This phase ... for biological membranes. Hexagonal II phase H sub II sub Lipid molecules in the HII phase ... possible that an outer monolayer of lipid coats the surface of the collection of tubes to protect ... tight packing of the lipid head groups reduces their contact with the aqueous phase. This, in turn ... on the lipid. These perturbations include pH changes, temperature changes, pressure changes, volume ... References J. M. Seddon, R. H. Templer. Polymorphism of Lipid Water Systems , from the Handbook of Biological ... more details
Refimprove date February 2011 Image Lipid raft organisation scheme.svg thumb 450px Lipid raft organisation, region 1 is standard lipidbilayer, while region 2 is a lipid raft. The plasma membrane of cells ... cite pmid 18955730 ref Lipid rafts are more ordered and tightly packed than the surrounding bilayer , but float freely in the membrane bilayer. ref cite pmid 12208858 ref Properties of lipid rafts ... in glycolipoprotein microdomains termed lipid rafts . ref Thomas S., Pais A.P., Casares S and Brumeanu T.D. 2004 . Analysis of lipid rafts in T cells. Molecular Immunology 41 399 409. http www.sciencedirect.com ... ref Thomas S., Kumar R.S. and Brumeanu.T.D 2004 . Role of lipid rafts in T cells. AITE 52 215 224. http ... a and cholesterol b . One key difference between lipid rafts and the plasma membranes from which they are derived is lipid composition. Research has shown that lipid rafts generally contain 3 to 5 fold the amount of cholesterol found in the surrounding bilayer. citation needed date February 2011 Also, lipid rafts are enriched in sphingolipid s such as sphingomyelin , which is typically elevated ... levels are decreased which results in similar choline containing lipid levels between the rafts ... contained in the rafts are more saturated and tightly packed than the surrounding bilayer. ref ... nature of the sterol group, cholesterol partitions preferentially into the lipid rafts where ..., Mahfoud R, Yahi N title Lipid rafts structure, function and role in HIV, Alzheimer s and prion diseases ... ref Rietveld & Simons related lipid rafts in model membranes to the immiscibility of ordered ... the two phases. Studies have shown there is a difference in thickness of the lipid rafts and the surrounding ... rafts into larger rafts, can also minimize line tension. ref name Pike By one early definition of lipid rafts, lipid rafts differ from the rest of the plasma membrane. In fact, researchers who date February 2011 have hypothesized that the lipid rafts can be extracted from a plasma membrane. The extraction ... more details
Unreferenced date December 2009 Orphan date November 2006 A simple lipid is a saponifiable lipid with just two types of components. When more components exist, the saponifiable lipid is classified as a complex lipid. See also Lipid Simple Lipids Esters of fatty acids with various alcohols. a. Fats Esters of fatty acids with glycerol. Oils are fats in the liquid state. b. Waxes Esters of fatty acids with higher molecular weight monohydric alcohols. Biochem stub DEFAULTSORT Simple Lipid Category Lipids ... more details
Lipid metabolism refers to the processes that involve the intercourse and degradation of lipid s. The types of lipids involved include Bile salt s Cholesterol s Eicosanoid s Glycolipid s Ketone bodies Fatty acids see also fatty acid metabolism Phospholipid s Sphingolipid s Steroid see also steroidogenesis Triacylglycerol s fats see also lipolysis and lipogenesis External links MeshName Lipid metabolism Ophardt, Charles E. 2003 http www.elmhurst.edu chm vchembook 622overview.html Lipid Catabolism Summary . Virtual Chembook. Elmhurst College. King, Michael W. http themedicalbiochemistrypage.org lipid synthesis.html Fatty Acid, Omega 3 and Omega 6 Fatty Acid, Triglyceride, and Phospholipid Synthesis and Metabolism . The Medical Biochemistry Page. http www.theheart.org condition lipid metabolic.do Breaking news and clinical trials about Lipid and Metabolism Metabolism Lipid metabolism enzymes Eicosanoid metabolism enzymes Glycolipid sphingolipid metabolism enzymes Ketone and cholesterol metabolism enzymes Category Lipids Category Metabolism biochemistry stub sr Lipidni metabolizam ... more details
1 IL 1 and a lipid soluble molecule that transports calcium ions Ca sup 2 sup across the bilayer ...Image signaling lipids2.png right thumb 400px Common lipid signaling molecules BR lysophosphatidic acid ... ethanolamine AEA Lipid signaling, broadly defined, refers to any biological cell signaling signaling event involving a lipid messenger that binds a protein target, such as a receptor biochemistry receptor ... responses. Lipid signaling is thought to be qualitatively different from other classical signaling ... through Cell membrane membranes see osmosis . One consequence of this is that lipid messengers cannot ... on demand at their intended site of action. As such, many lipid signaling molecules cannot circulate ... . Sphingolipid second messengers Main second messenger system Main sphingolipid File Second lipid messengers ... group from the sphingosine backbone. Alternatively, this sphingosine derived lipid sphingolipid .... J. Lipid Res . 46 , 2706 2716 2005 . ref It is also possible to regenerate sphingomyelin from ceramide ... for ceramide activation of serine threonine protein phosphatases. J. Lipid Res. 45 , 496 506 2004 ... kinases and phosphatases , and by inositol lipid metabolic pathways. ref Fugmann, T. et al. Regulation ... of bioactive lipid signalling lessons from Sphingolipids. Nature . 9 , 139 150 2008 . ref Sphingosine ... viability. J. Biol. Chem. . 278 , 34541 34547 2003 . ref Sphingosine is a single chain lipid usually ..., N. 2007 Prokazova, N. et al. Lipid second messengers and cell signaling in vascular wall. Biochemistry .... Adv. Lipid Res. 26 , 183 211 1993 . ref ref Gouaze Andersson, V. & Cabot, M. C. Glycosphingolipids ... blocks apoptosis through inhibition of acid sphingomyelinase in macrophages. J. Lipid Res. 45 .... 4 , 212 9 1992 . ref ref Nishizuka, Y. Protein kinase C and lipid signaling for sustained cellular ... lipids that activate cannabinoid receptors . The first such lipid to be isolated was anandamide ... Lipid signaling DEFAULTSORT Lipid Signaling Category Signal transduction ca Senyalitzaci lip dica ... more details
unreferenced date November 2011 Lipid profile or lipid test panel panel , is the collective term given to the estimation of, typically, cholesterol total cholesterol , high density lipoprotein high density lipoprotein cholesterol , low density lipoprotein low density lipoprotein cholesterol , and triglycerides . An extended lipid profile may include very low density lipoprotein . This is used to identify hyperlipidemia various disturbances of cholesterol and triglyceride levels , many forms of which are recognized risk factors for cardiovascular disease and sometimes pancreatitis . It is recommended that healthy adults with no other risk factors for heart disease be tested with a fasting lipid profile once every five years. citation needed date July 2011 Individuals may also be screened using only a cholesterol test and not a full lipid profile. However, if the cholesterol test result is high, there may be the need to have follow up testing with a lipid profile. citation needed date July 2011 If there are other risk factors or the individual has had a high cholesterol level in the past, regular testing is needed and the individual should have a full lipid profile. citation needed date July 2011 For children and adolescents at low risk, lipid testing is usually not ordered routinely. However, screening with a lipid profile is recommended for children and youths who are at an increased risk of developing heart disease as adults. Some of the risk factors are similar to those in adults and include a family history of heart disease or health problems such as diabetes, high blood pressure hypertension , or being overweight. High risk children should have their first lipid profile ... should also be measured. citation needed date July 2011 A lipid profile may also be ordered at regular intervals to evaluate the success of lipid lowering lifestyle changes such as diet and exercise ... References references External links http www.labtestsonline.org understanding analytes lipid glance.html ... more details
Image Lipid peroxidation.svg thumb 350px right Mechanism of lipid peroxidation. Lipid peroxidation refers to the redox oxidative degradation of lipid s. It is the process in which Radical chemistry free radicals steal electrons from the lipids in cell membranes , resulting in cell damage. This process proceeds by a free radical Chemical reaction chain reaction mechanism. It most often affects polyunsaturated fatty acids , because they contain multiple double bonds in between which lie methylene CH2 groups that possess especially reactive hydrogen s. As with any radical reaction, the reaction consists of three major steps initiation, propagation, and termination. Initiation Initiation is the step in which a fatty acid radical chemistry radical is produced. The most notable initiators in living cells are reactive oxygen species ROS , such as hydroxyl radical OH and HO2 , which combines with a hydrogen atom to make water and a fatty acid radical. Propagation The fatty acid radical is not a very stable molecule , so it reacts readily with molecular oxygen, thereby creating a peroxyl fatty ... fatty acid radical and a lipid peroxide, or a cyclic peroxide if it had reacted with itself ... doi abs 10.1111 j.1651 2227.1985.tb10987.x?journalCode apa Red Cell Membrane Lipid Peroxidation ... products of lipid peroxidation may be mutagenic and carcinogenic . ref name martnett For instance, the end ... to them, primarily M1G M sub 1 sub G . ref name martnett The toxicity of lipid hydroperoxides to animals .... These animals do not survive past embryonic day 8, indicating that the removal of lipid hydroperoxides ... of lipid peroxidation, to be specific, malondialdehyde MDA . ref name martnett http www.ncbi.nlm.nih.gov sites entrez?db pubmed&list uids 10064852&cmd Retrieve&indexed google Lipid peroxidation DNA damage ..., so this test is not completely specific for lipid peroxidation. ref name trevisan ... External links MeshName Lipid peroxidation DEFAULTSORT Lipid Peroxidation Category Fatty acids ... more details
Unreferenced date February 2008 A saponifiable lipid is one with an ester functional group, that can be hydrolysis hydrolyzed under basic conditions. These include triglyceride s, phospholipids , glycolipid s, sphingolipid s, and the wax es. These lipids are known as simple lipids . See also Lipids Category Lipids biochem stub ... more details
Prog. Lipid Res. volume 34 issue 4 pages 343 64 year 1995 pmid 8685243 doi 10.1016 0163 7827 95 00013 5 ref Accordingly, peroxisomal defects often lead to impairment of ether lipid production. Monoalkylglycerol ... by specific phospholipase s enzyme s might be involved in the generation of lipid second messenger ... cite journal author Spector A, Yorek M title Membrane lipid composition and cellular function url http www.jlr.org cgi reprint 26 9 1015 journal J Lipid Res volume 26 issue 9 pages 1015 35 date 1 September ... activating factor is an ether lipid signaling molecule that is involved in leukocyte function in the mammalian ... component a new class of lipid chemical mediators url http www.jbc.org cgi reprint 254 19 9355 journal ... 10.1042 BST0320147 ref Synthetic ether lipid analogs Synthetic ether lipid analogs have chemotherapy ... C . A toxic ether lipid analogue miltefosine has recently been introduced as an oral treatment ... with a particularly high ether lipid content in its membranes. ref cite journal author Lux H, Heise N, Klenner T, Hart D, Opperdoes F title Ether lipid alkyl phospholipid metabolism and the mechanism of action of ether lipid analogues in Leishmania journal Mol Biochem Parasitol volume 111 issue 1 ... more details
Infobox Disease Name Lipid pneumonia Image Caption DiseasesDB ICD10 ICD9 ICD9 516.8 ICDO OMIM MedlinePlus eMedicineSubj eMedicineTopic MeshID D011017 Lipid pneumonia or lipoid pneumonia is a specific form of lung inflammation pneumonia that develops when lipids enter the bronchial tree. The disorder is sometimes called Cholesterol pneumonia in cases where that lipid is a factor. ref cite journal author Pelz L, Hobusch D, Erfurth F, Richter K title Familial cholesterol pneumonia journal Helv Paediatr Acta year 1972 pages 371 9 volume 27 issue 4 pmid 4644274 ref Causes Sources of such lipids could be either exogenous or endogenous. ref name urlPulmonary Pathology cite web url http library.med.utah.edu WebPath LUNGHTML LUNG026.html title Pulmonary Pathology work accessdate 21 November 2008 ref Exogenous from outside the body. For example, inhaled nose drops with an oil base, or accidental inhalation of cosmetic oil. Amiodarone is an anti arrythmic known to cause this condition. Endogenous from the body itself, for example, when an airway is obstructed, it is often the case that distal to the obstruction, lipid laden macrophages Foam cell foamy macrophages and giant cells fill the lumen of the disconnected airspace. Appearance The gross appearance of a http www medlib.med.utah.edu WebPath LUNGHTML LUNG026.html lipid pneumonia is that in which there is an ill defined, pale yellow area on the lung. This yellow appearance explains the colloquial term golden pneumonia. At the microscopic scale foamy macrophages and giant cells are seen in the airways, and the inflammatory response is visible in the parenchyma. Treatment Treatment is with corticosteroids and possibly intravenous immunoglobulins . References reflist External links OMIM 215030 Respiratory pathology pneumonia Category Pneumonia use dmy dates date March 2012 ca Pneum nia lipo dal ... more details
Orphan date February 2009 Lipid therapy , fat therapy , or therapeutic lipovenous injections is a controversial medical technique that entails the injection and expulsion of fats and lipids, which proponents claim can improve cognitive and memory function. The technique recently gained notoriety, when it was revealed it had become a popular technique with French and Italian celebrities, and more recently a rumored handful of American celebrities. Description Patients who choose to undergo the controversial therapy are injected once a week for two months with a high density animal fat. Since most toxins in the body are fat soluble according to practitioners , this causes the patient to defecate a translucent slime, which is claimed to carry out the body s toxins, in turn boosting energy, increasing concentration, and improving memory. Many medical experts who oppose the technique have pointed out the slimy discharge how the body deals with any excess of intestinal and intravenous lipids, and it is a sign of high risk of artery damage and poor water absorption. Legal regulations sorting of any therapy as effective treatment for any condition is heavily restricted by law in many jurisdictions unless all such claims are scientifically validated. In the United States, for example, U.S. Food and Drug Administration regulations prohibit marketing any lipid therapy using medical claims, as such claims are unfounded. Additionally, clinicians and doctors who perform the therapy have drawn scrutiny from the Department of Agriculture for questionable documentation on their acquisition of the animal fat. Efficacy Double blind Blinding of patients and assessors to the therapy is difficult since lipid therapy can be easily discerned by the painful pressure in the thoracic cavity engendered by the sudden dip in plasma viscosity. Globules of lipid polymers also produce a significant shear ... of Lipids, Lipoproteins and Membranes . Elsevier, 2008. ISBN 0444532196 Yagi, Kunio. Lipid ... more details
The lipid hypothesis was one of two Hypothesis hypotheses the other being the chronic endothelial injury ... by the German pathologist Rudolf Virchow in 1856 and suggested that blood lipid accumulation ..., the lipid hypothesis received greater attention. An accumulation of evidence has led to the acceptance of the lipid hypothesis as scientific fact by the medical community ref name partv cite journal ... journal J. Lipid Res. volume 47 issue 7 pages 1339 51 year 2006 pmid 16585781 doi 10.1194 .... Lipid hypothesis of atherogenesis Early studies and origin In 1913, a study by Nikolai Anitschkow ..., Duff and McMillian formulated the lipid hypothesis in its modern form in a review which appeared ... century, the lipid hypothesis proposing that saturated fat s and cholesterol in the blood are a major ... validity. The interpretation of this research has resulted in the general acceptance of the lipid ... majority of researchers and practitioners were supportive of the validity of the lipid hypothesis ... trial ends it almost journal J Lipid Res date 2006 volume 47 pages 1 14 pmid 16227628 doi 10.1194 ..., the evidence accumulated through studies resulted in general acceptance of the lipid hypothesis ... volume 6 pages 36 37 pmid 9633288 issue 5 ref and by 2002, the lipid hypothesis was accepted by the scientific ... 1400040787 ref A minority of the medical community still argue that the lipid hypothesis has not yet ... downloads softsciencefat.pdf ref Nowadays, the term lipid hypothesis is commonly used by the opponents ... and 1980s, some researchers and practitioners considered the lipid hypothesis as unverified due ... for atherosclerosis. ref name Rifkind cite journal author Rifkind B, Levy R title Testing the lipid ... supporting it were flawed. ref name Oliver cite journal author Oliver M title Lipid lowering and ischaemic ... 6948505 ref ref name Stehbens88 cite journal author Stehbens W title Flaws in the lipid hypothesis ... 5 Pt 2 ref However, even after the Coronary Primary Prevention Trial ref cite journal title The Lipid ... more details
brominated lipid derivatives are able to quench the intrinsic tryptophan fluorescence from membrane proteins. The effiency of quenching depends on the distance between the lipid derivative and the fluorescent tryptophans. Perturbations of the lipidbilayer due to the presence of lateral membrane ... of proteins has little effect on either the order parameter of the lipids in the bilayer or the lipid ... lipid structures probed by waveguide spectroscopy and its application to study of supported lipidbilayer ... assignments are possible. Binding of peripheral membrane proteins to the lipidbilayer Many ...Orphan date April 2012 Protein lipid interaction is the influence of membrane protein s on the lipid ... proteins in the bilayer A large research effort involves approaches to know whether proteins have binding sites which are specific for particular lipids and whether the protein lipid complexes ... binding to specific membrane proteins. These involve the use of lipid analogues in reconstituted ... of the two components, a rapidly tumbling species in the bulk lipid phase with a sharp spectrum ... 7 sup sec sup 1 sup , 2 that the order parameters of the bound lipid are barely affected by being adjacent ... within lipid bilayers have been used to show how peptide and protein interactions can influence bilayer order, specifically demonstrating the real time association to bilayer and critical peptide concentration after which the peptides penetrate and disrupt the bilayer order. ref Tzong Hsien ... time quantitative analysis of lipid disordering by aurein 1.2 during membrane adsorption, destabilisation ... proteins. But there is a diverse group of proteins which interact directly with the surface of the lipidbilayer . Some, such as myelin basic protein, and spectrin have mainly structural roles. A number of soluble proteins can bind to the bilayer surface transiently or under specific conditions ... and stabilized by the lipid interaction. Misfolding processes, typically exposing hydrophobic regions ... more details
In lipid anchored proteins , a covalently attached fatty acid such as palmitate or myristate serves to anchor them to either face of the cell membrane . Examples include bacterial lipoproteins, G protein s and certain kinase s. It is believed that the fatty acid chain inserts and assumes a place in the lipidbilayerbilayer structure of the membrane alongside the similar fatty acid tails of the surrounding lipid molecules. Potential points of attachment include the terminal amino group of the protein backbone and the side chain of cysteine residues. Prenylation is the attachment of lipid chains to proteins to facilitate their interaction with the cell membrane . Some important prenylation chains are geranylgeraniol , farnesol and dolichol , all products of the HMG CoA reductase metabolic pathway . Other anchors include the GPI anchor see there . The bond is covalent. ref name Karp2009 cite book author Gerald Karp title Cell and Molecular Biology Concepts and Experiments url http books.google.com books?id arRGYE0GxRQC&pg PA128 accessdate 13 November 2010 year 2009 publisher John Wiley and Sons isbn 978 0 470 48337 4 pages 128 ref References Reflist Cell membranes DEFAULTSORT Lipid Anchored Protein Category Membrane biology Category Membrane proteins Category Lipoproteins Category Posttranslational modification Membrane protein stub sr Lipid vezani proteini ... more details
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