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Lipid Components (lipid + component)
Selected AbstractsSoil-borne wheat mosaic virus inclusion bodies: structural, compositional and staining propertiesANNALS OF APPLIED BIOLOGY, Issue 2 2003L J LITTLEFIELD Summary Anatomy and cytochemistry of inclusion bodies induced by Soil-borne wheat mosaic virus infection were studied in roots and leaves to learn more about the nature of inclusions and their roles in pathogenesis. Acid Fuchsin, Giemsa stain, Toluidine Blue and Trypan Blue stains facilitated visualization of inclusion bodies. Combined, simultaneous staining with Acid Fuchsin and Toluidine Blue clearly differentiated inclusion bodies from host nuclei. The overall anatomy, composition and structure of virus inclusions in leaves and roots were generally similar, as shown by phase contrast, differential interference contrast, epifluorescence, laser scanning confocal and transmission electron microscopy. Both were often closely associated with host nuclei; both were comprised of intertwined masses of tubular material, presumably endoplasmic reticulum, and in which varied numbers and sizes of vacuolar cavities occurred. Leaf inclusions, however, were typically larger and more vacuolate than those in roots. Lipids were found to be significant constituents of both the tubular and vacuolar components of inclusions, indicated by positive staining with Nile Red and Sudan Black. Inclusion bodies in both leaves and roots lost their structural and compositional integrity, eventually becoming disorganized and devoid of clearly identifiable components as host tissue aged and symptom expression advanced. Significant results of this study include the first published examination of virus inclusion bodies in root tissue, the degree of structural detail of inclusion body anatomy revealed by laser scanning confocal microscopy and the presence of an extensive lipid component in virus inclusion bodies. [source] Roasting effects on fatty acid distributions of triacylglycerols and phospholipids in sesame (Sesamum indicum) seedsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 7 2001Hiromi Yoshida Abstract Sesame seeds were roasted at different temperatures (180,220,°C) using a domestic electric oven. The positional distribution of fatty acids in triacylglycerols (TAGs) and phosphatidylcholine (PC) isolated from total lipids in these seeds was investigated as well as the naturally occurring antioxidants that are present. Major lipid components were TAGs and phospholipids (PLs), while steryl esters (SEs), free fatty acids (FFAs) and sn -1,3- and sn -1,2-diacylglycerols (DAGs) were minor ones. Following roasting, a significant increase (P,<,0.05) was observed in FFAs and in both forms of DAG (primarily sn -1,3-DAG). The greatest PL losses (P,<,0.05) were observed in phosphatidylethanolamine (PE), followed by PC and phosphatidylinositol (PI). On the other hand, the amounts of ,-tocopherol and sesamin remained at over 80 and 90% respectively of the original levels after roasting at 220,°C. The principal characteristics of the positional distribution of fatty acids were still retained after 25,min of roasting: unsaturated fatty acids, especially linoleic and/or oleic, were predominantly concentrated in the sn -2-position, and saturated fatty acids, especially stearic and/or palmitic, primarily occupied the sn -1- or sn -3-position. The results suggest that unsaturated fatty acids located in the sn -2-position are significantly protected from oxidation during roasting at elevated temperatures. © 2001 Society of Chemical Industry [source] In vitro, high-resolution 1H and 31P NMR based analysis of the lipid components in the tissue, serum, and CSF of the patients with primary brain tumors: one possible diagnostic viewNMR IN BIOMEDICINE, Issue 2 2010Niraj Kumar Srivastava Abstract In vitro, high-resolution 1H and 31P NMR based qualitative and quantitative analyses of the lipid components of the tissue, serum, and CSF of patients with primary brain tumors were performed. Proton NMR spectra of the lipid extract of serum (blood specimen collected before the surgical procedure) and surgically discarded tissue showed that the total cholesterol (T.CHOL) and choline containing phospholipids (PL) were significantly higher in quantity in medulloblastoma and glioblastoma multiforme as compared to normal subjects. Serum lipid extracts of grade II/ III gliomas showed a higher quantity of PL than normal subjects. Cholestrol esters (CHOLest) were detectable in the tissue lipid extract of the patients with tumors and absent in normal tissue. There was a reduction in the quantity of CHOLest in the serum lipid extract of the tumor patients as compared to normal subjects. Ratio of PL to T.CHOL in serum lipid extract showed a significant difference between different grades of tumors versus normal subjects, while, a significant difference was observed only in medulloblastoma versus normal subjects in tissue lipid extract. Ratio of CHOL to CHOLest distinguishes the different grades of tumors versus normal subjects as well as between different grades of tumors (except medulloblastoma versus glioblastoma). The ratio of the Ph (total phospholipids except phosphatidylcholine) to PC (phosphatidylcholine) in 31P NMR based study showed a significant difference in all grades of tumors (except medulloblastoma) in normal subjects in tissue lipid extract as well as between different grades of tumors. Medulloblastoma could be differentiated from glioblastoma as well as from normal subjects in serum lipid extract by the ratio of the Ph to PC. Proton NMR spectra of the lipid extract of CSF showed that the CHOL, CHOLest, and PL were present in the patients with tumors, although these were absent in the patients with meningitis, motor neuron disease, and mitochondrial myopathies as well as in normal subjects. PL and T.CHOL provided discrimination between different grades of tumors (except glioblastoma versus medulloblastoma) in the lipid extract of the CSF. This study suggests the role of lipid estimation in CSF and serum as a complementary diagnostic tool for the evaluation of brain tumors preoperatively. NMR-based lipid estimation of post-surgical tumor tissue may also contribute to differentiating the tumor types. Copyright © 2009 John Wiley & Sons, Ltd. [source] Novel corrective equations for complete estimation of human tissue lipids after their partial destruction by perchloric acid pre-treatment: high-resolution 1H-NMR-based studyNMR IN BIOMEDICINE, Issue 2 2008Niraj Kumar Srivastava Abstract Owing to the small quantity of tissue available in human biopsy specimens, aqueous and lipid components often have to be determined in the same tissue sample. Perchloric acid (PCA) used for the extraction of aqueous metabolites has a deleterious effect on lipid components; the severity of the damage is not known. In this study, human muscle tissue was first treated with PCA to extract aqueous metabolites, and the residue was then used for lipid extraction by conventional methods, i.e. the methods of Folch and Bligh & Dyer and a standardised one using methanol/chloroform (1:3, v/v) used in our laboratory. A 1H-NMR spectrum was obtained for each lipid extract. Lipid was quantified by measuring the integral area of N+ -(CH3)3 signals of phospholipids (PLs). Triacylglycerol (TG) and cholesterol (CHOL) were quantified using the -CH2 - signals of glycerol and the C18 methyl signal, respectively. This study shows that prior use of PCA caused marked attenuation of TG, PL, and CHOL. This was confirmed by recovery experiments and observation of the direct effect of PCA on the standard lipid components. On the basis of the quantity of lipid lost in each case, three novel equations (with respect to TG, PL, and CHOL) were derived. Application of these equations to lipid quantities estimated in different pathological tissues after PCA pre-treatment produced values equivalent to those estimated without PCA use. This study conclusively shows that PCA pre-treatment damages all three lipid moieties, TG, PL, and CHOL. When PCA is used in a fixed ratio to the tissue, the lipid damage is also proportional and correctable by statistically derived equations. These equations will be useful in human biopsy specimens where aqueous and lipid components have to be studied using the same tissue sample because of the small quantity available. Copyright © 2007 John Wiley & Sons, Ltd. [source] In vitro1H NMR studies of RD human cell infection with echovirus 11NMR IN BIOMEDICINE, Issue 4 2007S. Naved Akhtar Abstract The effects of echovirus 11 infection on RD human cell line (derived from rhabdomyosarcoma) were studied using 1H NMR spectroscopy and optical microscopy. Both uninfected and infected cells consumed glucose and produced lactate, acetate and formate as extracellular metabolites. In infected whole cells, phosphocholine and uridine-sugar were observed in addition to the metabolites observed in uninfected cells. Water-soluble intracellular metabolites of infected cells showed glutamine, phosphocholine and glycine which were not observed in uninfected cells. Cellular metabolites except lipid components gradually decreased and disappeared during 24,48,h of viral infection. The quantity of lipid components in infected cells was comparable with that in uninfected cells, indicating that echovirus 11 does not utilize cell lipid molecules. Unlike optical microscopy, 1H NMR spectroscopy identified early stages of infection through metabolic changes. These results may have potential implications in probing virus,cell interactions using NMR-based metabolomics. Copyright © 2006 John Wiley & Sons, Ltd. [source] Properties of plant plasma membrane lipid models , bilayer permeability and monolayer behaviour of glucosylceramide and phosphatidic acid in phospholipid mixturesPHYSIOLOGIA PLANTARUM, Issue 2 2000Anna H. Berglund Phosphatidic acid (PA) and glucosylceramide (Cer), constituents of plant plasma membranes, were used in interaction studies with the major plasma membrane lipid components, phosphatidylcholine (PC) and phosphatidylethanolamine (PE). With molecular species combinations, representative for plant plasma membranes, packing conditions during compression of monolayers of PC/PE mixtures with different amounts of PA or Cer added, were investigated. In contrast to the behaviour of single PA or single Cer, which exhibited condensed compression curves, as compared with curves representative for phosphoglycerides, the triple mixtures of PC/PE with PA or Cer showed markedly expanded monolayer films. These data were evaluated as a spontaneous heterogeneous dispersion of PA and Cer in the PC/PE mixture. Membrane vesicles produced with different amounts of PA added to a PC/PE mixture of 1:1 (mol/mol) had an almost linear increase in permeability for glucose (chosen as a common polar low-molecular mass metabolite) with increasing percentage PA. The presence of PA in plasma membranes and its possible function are discussed in relation to recent reports on anionic protein-lipid interactions. PC/PE vesicles with different amounts of Cer added did not influence the permeability for glucose at 2.5 and 5 mol%, but did so, significantly, at 7.5 and 9 mol%. [source] 4133: Dry eye and human tear lipid compositional, conformational and functional relationships using spectroscopyACTA OPHTHALMOLOGICA, Issue 2010D BORCHMAN Purpose Knowledge of the relationships among composition, conformation and function of tear film lipids could facilitate the development of therapies to alleviate symptoms related to meibomian gland dysfunction (MGD) and to diagnose the disease. Toward this goal, we used spectroscopic approaches to assess tear lipid composition and conformation relationships with age, sex and meibomian gland dysfunction. Methods Spectra of meibum from 41 patients diagnosed with MGD (Md) and 27 normal donors (Mn) were acquired. Results 1H-NMR spectra showed cholesterol esters were found to decrease by 21% with MGD. The number of double bonds/ester increased with age and MGD which indirectly relates to tear film stability. With age, the amount of CH2 groups increased twice as much as the C=C moieties and the C=C/CH2 and CH3/CH2 ratios were related to lipid order and indirectly related to meibum delivery. With the use of MALDI-TOF MS, we quantified and identified lipid components in Mn and Md such as cholesterol, hydrocarbons and wax esters with a sensitivity of 9 pmoles for each analyte. Sixty-nine of the 189 resolved peaks were unique to Md spectra compared to Mn spectra and were not due to waxes. Extra peaks in Md spectra may arise from increased lipid synthesis, bacteria or cellular debris. Conclusion It is reasonable that as the lipids become more ordered and more viscous with Md, less lipid flows out of the meibomian gland orifice and more casual lipid is present on the lid margin. The age- and disease-related changes in the physical and chemical characteristics of meibum lipids suggest that the C=C/CH2 and CH3/CH2 ratios may be more important than quantity in relation to tear film stability. 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