bluuebunny/crossref_metadata_2025_split huggingface dataset:
Supramolecular aggregations through the inclusion complexation of cyclodextrins and polymers with bulky end groups
Authors: Chan Shih‐Chi , Kuo Shiao‐Wei , She Hwo‐Shuenn , Lin Ho‐May , Lee Hsin‐Fang , Chang Feng‐Chih 
Published: November 2006

AbstractMono‐polyhedral oligomeric sillsesquioxane‐end capped poly(ε‐caprolactone) (mPPCL) can form inclusion complexes (ICs) with α‐ and γ‐cyclodextrins (CDs) but not with β‐CD. These CD ICs have been characterized with X‐ray diffraction, solid‐state 13C cross‐polarization/magic‐angle‐spinning NMR spectroscopy, 1H NMR spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and scanning electron microscopy. The poly(ε‐caprolactone) (PCL) chain of mPPCL is included within the channel provided by the CDs to form a columnar, crystalline structure. The PCL/CD ratios determined by 1H NMR spectroscopy for the ICs with α‐ or γ‐CDs are higher than the stoichiometries because of the steric hindrance of the bulky polyhedral oligomeric silsesquioxane chain end and result in a fraction of the ε‐caprolactone units free from complexation with the CDs. On the basis of these analyses, we propose some possible structures for these CD/mPPCL ICs. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 125–135, 2007
Effect of palm oil carotene on breat cancer tumorigenicity in nude mice
Authors: Nesaretnam Kalanithi , Radhakrishnan Ammu , Selvaduray Kanga Rani , Reimann Karin , Pailoor Jayalakshmi , Razak Ghazali , Mahmood Mina Mustafa , Dahliwal Jasbir Singh 
Published: November 2006

AbstractBiological therapies are new additions to breast cancer treatment. Among biological compounds, β‐carotene has been reported to have immune modulatory effects, in particular, enhancement of natural killer cell activity and tumor necrosis factor‐alpha production by macrophages. The objective of this study was to investigate the effect of palm carotene supplementation on the tumorigenicity of MCF‐7 human breast cancer cells injected into athymic nude mice and to explore the mechanism by which palm carotenes suppress tumorigenesis. Forty‐eight 4‐wk‐old mice were injected with 1×106 MCF‐7 cells into their mammary fat pad. The experimental group was supplemented with palm carotene whereas the control group was not. Significant differences were observed in tumor incidence (P<0.001) and tumor surface area and metastasis to lung (P<0.005) between the two groups. Natural killer (NK) cells and B‐lymphocytes in the peripheral blood of carotene‐supplemented mice were significantly increased (P<0.05 and P<0.001, respectively) compared with controls. These results suggest that palm oil carotene is able to modulate the immune system by increasing peripheral blood NK cells and B‐lymphocytes and suppress the growth of MCF‐7 human breast cancer cells.
Transfer of lipids between hemolymph and hepatopancreas in the shrimp Macrobrachium borellii
Authors: García Fernando , González‐Baró María , Pollero Ricardo 
Published: November 2006

AbstractCrustancean lipids are transported in the hemolymph by an HDL. The hepatopancreas is the most important and active organ regarding lipid metabolism, so we studied the interchange of FA and acylglycerols between both components of the hepatopancreas‐hemolymph system in the decapod crustacean Macrobrachium borellii. The hepatopancreas and a sole plasma lipoprotein were labeled by in vivo incubations with 14C palmitic acid injected into the hemolymph. Then they were incubated in vitro with unlabeled hepatopancreas and hemolymph, and the transfer of lipids between them was measured by radiochromatographic techniques. It was determined in vivo that more than 80% of the circulating palmitic acid was taken up by the hepatopancreas and incorporated into PC and TAG. Both classes of lipids, but mainly PC, were transferred back from tissues to the hemolymph. Lipid transfer was also demonstrated in vitro. The transfer of PC (30% of labeling) as well as that of FFA (48% of labeling) from hemolymph to hepatopancreas was determined. On the other hand, FFA were released more efficiently than the acylglycerols from intact hepatopancreas to hemolymph, and they were the only lipid transferred when the hepatopancreas had been previously washed.
Effects of dietary conjugated linoleic acid on the expression of uncoupling proteins in mice and rats
Authors: Ealey Kafi N. , El‐Sohemy Ahmed , Archer Michael C. 
Published: November 2006

AbstractCLA inhibits mammary cancer and reduces body fat accumulation in rodents. It is not known whether uncoupling proteins (UCP), which are modulators of energy balance and metabolism, play a role in these actions of CLA. To determine the effects of dietary CLA on the expression of UCP in various tissues, 5‐wk‐old Sprague‐Dawley rats and C57BI/6 mice were fed diets containing 1% CLA for 3 wk. CLA treatment reduced adipose depot weights in both rats and mice but had no significant effects on body weight. There was a species‐specific effect of CLA on the expression of UCP. Whereas CLA did not affect the expression of UCP in most tissues in rats, mice fed CLA had increased expression of UCP2 in the mammary gland, brown adipose tissue (BAT), and white adipose tissue (WAT). Furthermore, UCP1 and UCP3 mRNA and protein levels in BAT were significantly lower in CLA‐fed mice compared to controls. Skeletal muscle UCP3 mRNA was unchanged, but UCP3 protein levels were significantly increased in mice, suggesting translational or posttranslational regulation of this protein. Results from this study suggest that alterations in the expression of UCP in mice may be related to the previously reported effects of dietary CLA in lowering adiposity and increasing FA oxidation. In rats, however, induction of UCP is not likely to be responsible for fat reduction or for the inhibitory action of CLA on mammary carcinogenesis.
Lipids and Δ6‐desaturase activity alterations in rat liver microsomal membranes induced by fumonisin B1
Authors: Gelderblom W. C. A. , Moritz W. , Swanevelder S. , Smuts C. M. , Abel S. 
Published: November 2006

AbstractAlterations in the membrane structure and function of hepatocyte membranes by fumonisin B1 (FB1) have been proposed to play an important role in the disruption of growth regulatory effects and hence in the cancer‐promoting ability of the mycotoxin. Detailed analyses of lipids in liver microsomal fractions of rats exposed to different dietary levels of FB1 over a period of 21 d indicated an increase in PC, PE, PI, and cholesterol (Chol). These changes decreased the PC/PE and increased the total phospholipid/Chol ratios. When considering FA content, the quantities of total FA increased (P<0.05) in the major phospholipid fractions as a result of the increased phospholipid levels. However, when considering the relative levels (mg/100 mg of the total FA) of specific FA, the monounsaturated FA (16∶1n−7 and 18∶1n−9) and 18∶2n−6 increased (P<0.05), whereas the long‐chain PUFA decreased (P<0.05) in the main phospholipid fractions. Enzyme analyses indicated that the activity of the Δ6‐desaturase was significantly reduced in liver microsomal preparations in a dose‐dependent manner. An increase in the 20∶3n−6/20∶4n−6 ratio also suggested a decrease in the activity of the Δ5‐desaturase. Disruption of microsomal lipid metabolism at different levels by FB1 could play an important role in the alteration of growth regulatory effects in the liver.
Destabilizing effects of fructose‐1,6‐bisphosphate on membrane bilayers
Authors: Ehringer William D. , Su Susan , Chiang Benjamin , Stillwell William , Chien Sufan 
Published: November 2006

AbstractFructose‐1,6‐bisphosphate (FBP) is a high‐energy glycolytic intermediate that decreases the effects of ischemia; it has been used successfully in organ perfusion and preservation. How the cells utilize external FBP to increase energy production and the mechanism by which the molecule crosses the membrane bilayer are unclear. This study examined the effects of FBP on membrane bilayer permeability, membrane fluidity, phospholipid packing, and membrane potential to determine how FBP crosses the membrane bilayer. Large unilamellar vesicles composed of egg phosphatidylcholine (Egg PC) were made and incubated with 50 mM FBP spiked with 14C‐FBP at 30°C. Uptake of FBP was significant (P<0.05) and dependent on the lipid concentration, suggesting that FBP affects membrane, bilayer permeability. With added calcium (10 mM), FBP uptake by lipid vesicles decreased significantly (P<0.05). Addition of either 5 or 50 mM FBP led to a significant increase (P<0.05) in Egg PC carboxyfluorescein leakage. We hypothesized that the membrane‐permeabilizing effects of FBP may be due to a destabilization of the membrane bilayer. Small unilamellar vesicles composed of dipalmitoyl pC (DPPC) were made containing either diphenyl‐1,3,5‐hexatriene (DPH) or trimethylammmonia‐DPH (TMA‐DPH) and the effects of FBP on the fluorescence anisotropy (FA) of the fluorescent labels examined. FBP caused a significant decrease in the FA of DPH in the liquid crystalline state of DPPC (P<0.05), had no effect on FA of TMA‐DPH in the liquid crystalline state of DPPC, but increased the FA of TMA‐DPH in the gel state of DPPC. From phase transition measurements with DPPC/DPH or TMA‐DPH, we calculated the slope of the phase transition as an indicator of the cooperativity of the DPPC molecules. FBP significantly decreased the slope, suggesting a decrease in fatty acyl chain interaction (P<0.05). The addition of 50 mM FBP caused a significant decrease (P<0.05) in the liquid crystalline/gel state fluorescence ratio of merocyanine 540, indicating increased head‐group packing. To determine what effects these changes would have on cellular membranes, we labeled human endothelial cells with the membrane potential probe 3,3′‐dipropylthiacarbocyanine iodide (DiSC3) and then added FBP. FBP caused a significant, dose‐dependent decrease in DiSC3 fluorescence, indicating membrane depolarization. We suggest that FBP destabilizes membrane bilayers by decreasing fatty acyl chain interaction, leading to significant increases in membrane permeability that allow FBP to diffuse into the cell where it can be used as a glycolytic intermediate.
Simultaneous determination by GC‐MS of epoxy and hydroxy FA as their methoxy derivatives
Authors: Wilson R. , Lyall K. 
Published: November 2006

AbstractWe report on a capillary GC‐MS method for the quantitative analysis of hydroxy and epoxy FA. Catalytic hydrogenation of lipid extracts produces stable saturated lipids. Saponification followed by methylation with boron trifluoride in the presence of methanol converts FA to methyl esters and epoxy groups to methoxy‐hydroxy groups. These compounds are purified from nonoxidized methyl esters using solid phase extraction. Derivatization of the hydroxy group using tetramethylammonium hydroxide forms methoxy and vicinal dimethoxy FAME. When subjected to El‐MS, fragmentation gives two characteristic ion fragments for each epoxy and hydroxy positional isomer. Quantitative measurements were achieved using uniformly labeled hydroxy and epoxy 13C FA as internal standards. Epoxy and hydroxy FA were identified in both plasma and adipose tissue of men, and the levels of hydroxy and epoxy in these tissues were related. The levels of hydroxy isomers were typical of oxidation of linoleic acid, whereas epoxy isomers were characteristic of oxidation of oleic acid.
Apolipoproteins A‐I and A‐II downregulate neutrophil functions
Authors: Furlaneto Cristiane Jaciara , Ribeiro Fernanda Pereira , Hatanaka Elaine , Souza Glaucia Mendes , Cassatella Marco A. , Campa Ana 
Published: November 2006

AbstractThis work reports the effect of the apolipoproteins A‐I and A‐II (apoA‐I and apoA‐II) on the release of tumor necrosis factor (TNF)‐α, interleukin (IL)‐1β, IL‐8, and IL‐1 receptor antagonist (IL‐1Ra) and on the oxidative burst of human neutrophils. By themselves, apoA‐I and apoA‐II do not affect the basal liberation of these cytokines, whereas apoA‐I affects the release of IL‐1β from lipopolysaccharide (LPS)‐stimulated neutrophils and apoA‐II affects IL‐8 released from LPS‐stimulated neutrophils. ApoA‐II also decreases the production of IL‐8 released by neutrophils stimulated with the acute phase apolipoprotein serum amyloid A. Both apoA‐I and apoA‐II exerted ∼30% inhibition on the oxidative burst of neutrophils stimulated by opsonized zymosan, as revealed by the luminol‐enhanced chemiluminescence assay. These findings give additional support to the idea that the role of human plasma lipoproteins and apolipoproteins goes beyond their function in lipid transport and metabolism. HDL apolipoproteins appear to be a class of mediators that can participate in the regulation of the activity of neutrophils.
Purification of lipoxygenase from Chlorella: Production of 9‐ and 13‐hydroperoxide derivatives of linoleic acid
Authors: Nuñez Alberto , Savary Brett J. , Foglia Thomas A. , Piazza George J. 
Published: November 2006

AbstractOxygenation of linoleic acid by the enzyme lipoxygenase (LOX) that is present in the microalga Chlorella pyrenoidosa is known to produce the corresponding 9‐and 13‐hydroperoxide derivatives of linoleic acid (9‐ and 13‐HPOD, respectively). Previous work with this microalga indicated that partially purified LOX, present in the 30–45 and 45–80% saturated (NH4)2SO4 precipitate fractions, produced both HPOD isomers but in different ratios. It was not clear, however, if the observed activity in the two isolates represented the presence of one or more isozymes. In the present work, LOX isolated from the intracellular fraction of Chlorella by (NH4)2SO4 precipitation (35–80% saturated) was purified by ion exchange and hydrophobic interaction chromatography to apparent homogeneity. Analysis of the purified protein by SDS‐PAGE and subsequent native size exclusion chromatography demonstrated that LOX in Chlorilla is a single monomeric protein with a molecular mass of approximately 47 kDa. The purified LOX produced both the 9‐HPOD and 13‐HPOD isomers from linoleic acid in equal amounts, and the isomer ratio was not altered over the pH range of 6 to 9. Optimal activity of LOX was at pH 7.5.
Olive oil phenolics protect LDL and spare vitamin E in the hamster
Authors: Wiseman Sheila A. , Tijburg Lilian B. M. , van de Put Frans H. M. M. 
Published: November 2006

AbstractAn animal feeding trial was conducted to investigate whether olive oil phenolics can act as functional antioxidants in vivo. To this end, hamsters were exposed for a period of 5 wk to a dietary regime with either a phenol‐rich extra virgin olive oil or extra virgin olive oil from which phenols were removed by ethanol/water‐washing. The original oil used in the high olive phenol diet was also used for the preparation of the low phenol diet in order to keep the FA compositions exactly the same. In addition, the vitamin E content was kept identical in both diets. This careful preparation of the diets was undertaken in order to prevent these factors from influencing the antioxidative status in plasma and LDL. Removal of olive oil phenols was shown to reduce both the vitamin E level in plasma and the resistance of LDL to ex vivo oxidation. The results of this study support the idea that extra virgin olive oil phenols improve the antioxidant defense system in plasma by sparing the consumption of vitamin E under normal physiological circumstances.
FA composition of cholesteryl esters and phospholipids in maternal plasma during pregnancy and at delivery and in cord plasma at birth
Authors: De Vriese S. R. , Dhont M. , Christophe A. B. 
Published: November 2006

AbstractThe purpose of this study was to assess the FA composition of both cholesteryl esters (CE) and phospholipids (PL) in maternal plasma during pregnancy and at delivery and in umbilical plasma at birth. A longitudinal study of 32 normal pregnant women was carried out with three cutoff points during pregnancy (first, second, and third trimester) and at delivery. Few significant differences occurred in the FA profile of maternal CE: 18∶1n−9 increased, 18∶2n−6 dropped slightly, and 18∶3n−3 decreased with progressing gestation. In maternal PL, long‐chain highly unsaturated FA concentrations dropped and were replaced by saturated FA as gestation progressed. Additionally, changes in saturated FA in PL occurred: Shorter‐chain 16∶0 was higher whereas longer‐chain 18∶0 was lower at delivery compared to early pregnancy. The FA profile of umbilical venous plasma was strikingly different from that of maternal plasma at delivery. Cord plasma CE contained more saturated and monounsaturated FA than maternal CE. The polyunsaturates 18∶2n−6 and 18∶3n−3 are lower in umbilical CE than in maternal CE whereas 20∶4n−6 and 22∶6n−3 are twice as high in umbilical CE. Cord plasma PL have a higher content of long‐chain highly unsaturated FA than maternal plasma PL at delivery. In contrast to maternal plasma PL, 16∶0 was lower and longer‐chain saturated FA were higher in cord plasma PL. The FA profile of umbilical plasma at birth shows preferential accumulation of 20∶4n−6 and 22∶6n−3, with low concentrations of 18∶2n−6 and 18∶3n−3 in CE and PL, indicating a preferential supply of the fetus with long‐chain highly unsaturated FA needed for fetal development.
Acute elevations of medium‐and long‐chain fatty acids have different impacts on endothelium‐dependent vasodilation in humans
Authors: Steer Peter , Basu Samar , Lithell Hans , Vessby Bengt , Berne Christian , Lind Lars 
Published: November 2006

AbstractIt has previously been shown that acute elevation of long‐chain fatty acids (LCFA) impairs endothelium‐dependent vasodilation (EDV) in humans. In this study, we tested the hypothesis that an elevation of both medium‐chain fatty acids (MCFA) and LCFA affects the endothelium differently from LCFA elevation alone. Ten healthy volunteers received an intravenous infusion of Structolipid≿ (structured TG, MCFA/LCFA ratio 1∶1) and heparin for 2 h, while another 10 subjects received an infusion of Intralipid≿ (LCFA only) and heparin. EDV and endothelium‐independent vasodilation (EIDV) were studied in the forearm after local administration of methacholine chloride (2 and 4 μg/min) and sodium nitroprusside (5 and 10 μg/min). Forearm blood flow was determined by venous occlusion plethysmography. Intralipid and heparin increased circulating FA levels from 0.2±0.1 to 1.4±0.5 mmol/L (P<0.001) and reduced EDV by 20% (P<0.01). Although Structolipid and heparin increased circulating FA levels to a similar extent (from 0.4±0.1 to 1.8±0.4 mmol/L after 2 h), EDV was not significantly changed. EIDV increased slightly during both interventions (P<0.05). In conclusion, an acute elevation of LCFA attenuated EDV, whereas an elevation of both MCFA and LCFA did not influence EDV. Thus, FA composition seems to be of importance for EDV in healthy humans.
Very long chain PUFA in murine testicular triglycerides and cholesterol esters
Authors: Furland Natalia E. , Maldonado Eduardo N. , Aveldaño Marta I. 
Published: November 2006

AbstractVery long chain (VLC) PUFA of the n−6 and n−3 series are known to occur in mammalian testis. The aim of this work was to characterize further two testicular lipid classes with VLCPUFA, cholesterol esters (CE) and total triglycerides (TG) in rat and mouse testis. The VLCPUFA predominating in these lipids were a series of n−6 pentaenes and tetraenes with 24 to 32 carbons, including small amounts of odd‐chain PUFA, 28∶5n−6 and 24∶5n−6 prevailing in CE and TG, respectively. Most of the VLCPUFA of TG were concentrated in a small fraction of TG, made up by 1‐O‐alkyl‐2,3‐DAG. This TG subclass was absent altogether from the TG of sexually immature testis. The TG and the CE with VLCPUFA only occurred in testis of adult fertile animals. The proportion of VLCPUFA in total TG and CE was higher in rodents than in other mammals. In the n−6 PUFA‐rich adult mouse testis, the amounts of testicular triacylglycerols decreased significantly after consumption of fish oil for 2 wk. Whereas 18∶2n−6 was significantly reduced, the amounts of 22∶5n−6 and longer n−6 PUFA were less affected in all mamor testicular lipids including PC and PE, where they were unchanged. The 1‐O‐alkyl‐2,3‐DAG and their n−6 VLCPUFA were virtually unaffected by the diet. The VLCPUFA‐containing molecular species of CE and TG may represent a form of storage of cholesterol and polyenoic FA required to sustain spermatogenesis. Via chain‐shortening, VLCPUFA stored in the neutral lipids may serve as precursors of the major C22 PUFA typical of cell membrane glycerophospholipids, protecting testicular cells against shifts in FA composition induced by dietary changes.
Phospholipid FA from indian ocean tunicates Eudistoma bituminis and Cystodytes violatinctus
Authors: Viracaoundin I. , Barnathan G. , Gaydou E. M. , Aknin M. 
Published: November 2006

AbstractTwo tunicates (Fudistoma bituminis and Cystodytes violatinctus, family Polycitoridae) were investigated for the FA content of their phospholipids. GC‐MS analysis of their methyl esters and N‐acyl pyrrolidides revealed 40 FA in E. bituminis, and 26 in C. violatinctus. In both cases, the most abundant FA were the saturated ones (C10 to C18). Cystodytes violatinctus contained considerable oleic acid (20%). Both E. bituminis and C. violatinctus contained phytanic acid and Δ10‐unsaturated FA, which had not previously been found in such organisms. The two tropical tunicates contained only trace amounts of PUFA, which are usually predominant in this phylum.
Cloning of an alkaline lipase gene from Penicillium cyclopium and its expression in Escherichia coli
Authors: Wu Minchen , Qian Zhikang , Jiang Peihong , Min Taishan , Sun Chongrong , Huang Weida 
Published: November 2006

AbstractThe gene encoding an alkaline lipase of Penicillium cyclopium PG37 was cloned with four steps of PCR amplification based on different principles. The cloned gene was 1,480 nucleotides in length, consisted of 94 bp of promoter region, and had 6 exons and 5 short introns ranging from 50 to 70 nucleotides. The open reading frame encoded a protein of 285 amino acid residues consisting of a 27‐AA signal peptide and a 258‐AA mature peptide, with a conserved motif of Gly‐X‐Ser‐X‐Gly shared by all types of alkaline lipases. However, this protein had a low homology with lipases of P. camembertii (22.9%), Humicola lanuginosa (25.6%), and Rhizomucor miehei (22.3%) at the amino acid level. The mature peptide‐encoding cDNA was cloned and expressed in Escherichia coli on pET‐30a for confirmation. A distinct band with a M.W. of 33 kDa was detected on SDS‐PAGE. Results of a Western blot analysis and an enzyme activity assay verified the recombinant 33‐kDa protein as an alkaline lipase. Its catalytic properties were not changed when compared with its natural counterpart.
Antioxidant action of a lipophilic nitroxyl radical, cyclohexane‐1‐spiro‐2′‐(4′‐oxyimidazolidine‐1′‐oxyl)‐5′‐spiro‐1″‐cyclohexane, against lipid peroxidation under hypoxic conditions
Authors: Shimakawa Shuichi , Yoshida Yasukazu , Niki Etsuo 
Published: November 2006

AbstractNitroxyl radicals are known to act as radical scavenging antioxidants. In the present study, a lipophilic nitroxyl radical, cyclohexane‐1‐spiro‐2′‐(4′‐oxyimidazolidine‐1′‐oxyl)‐5′‐spiro‐1″‐cyclohexane (nitroxyl radical I) was synthesized and its antioxidant capacity was assessed in comparison with a hydrophilic nitroxyl radical, 4‐hydroxy‐2,2,6,6‐tetramethylpiperidine‐N‐oxyl (Tempol). Both nitroxyl radical I and Tempol inhibited methyl linoleate oxidation induced by free radicals, and the efficacy increased with decreasing partial pressure of oxygen, the effect being more pronounced for nitroxyl radical I than Tempol. Their hydroxylamines inhibited lipid peroxidation more effectively than their corresponding parent nitroxyl radicals. In liposomal membranes, a synergistic effect was observed in the combination of nitroxyl radical I with ascorbic acid, whereas only an additive effect was observed between Tempol and ascorbic acid. The present study suggests that nitroxyl radical I and its hydroxylamine may act as potent antioxidants, especially in combination with ascorbic acid under hypoxic conditions.