bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determining the relative amounts of positional isomers in complex mixtures of triglycerides using reversed‐phase high‐performance liquid chromatography‐tandem mass spectrometry
Authors: Malone Michael , Evans Jason J. 
Published: November 2006

AbstractA reversed‐phase HPLC‐tandem mass spectrometry (RP‐HPLC‐MS‐MS) method was refined for the positional analysis of complex mixtures of TAG. This method has the advantages of speed, ease of automation, and specificity over traditional digestion‐based methods for the positional analysis of TAG. Collision‐induced dissociation (CID) of ammoniated TAG in an ion‐trap mass spectrometer produced spectra that were dependent on the FA position. Dominant DAG fragments were formed from the loss of a FA moiety from the ammoniated TAG species. The loss of FA in the outer positions was favored over their loss in the central position. The combination of RP‐HPLC and CID produced spectra that were free of the isotope effects that can complicate spectral interpretation in existing methods. The combination also provided selectivity based on the chromatographic fractionation of TAG, in addition to the selectivity inherent in the CID process. Proof‐of‐concept experiments were performed with binary mixtures of TAG from the SOS/SSO, OSO/OOS, and the PSO/POS/SPO positional isomer systems (where S is 18∶0, stearic acid; O is 18∶1 (cis‐9), oleic acid; and P is 16∶0, palmitic acid). Plots of fractional DAG fragment intensities vs. fractional composition of the binary mixtures were linear. These plots were used to determine the fractional composition of each of these isomeric systems in a variety of vegetable oils and animal fats. Current limitations, future developments, and applications of this method are discussed.
An efficient and novel method for the synthesis of cardiolipin and its analogs
Authors: Lin Zhen , Ahmad Moghis U. , Ali Shoukath M. , Ahmad Imran 
Published: November 2006

AbstractA novel synthetic method has been developed for cardiolipin and its analog via a chlorophosphoramidite coupling reaction followed by oxidation. The reagent, N,N‐diisopropylmethylphosphoramidic chloride, couples effectively with 1,2‐O‐dimyristoyl‐sn‐glycerol in the presence of an amidite activator to form a phosphoamidite intermediate, which then reacts with 2‐O‐benzylglycerol in the presence of a basic catalyst followed by in situ oxidation to give the corresponding protected cardiolipin. Deprotection of the protecting groups provides tetramyristoyl cardiolipin in good overall yield of 60%. The synthetic method is applicable to large‐scale synthesis of cardiolipin and various analogs with or without unsaturation for liposomal drug delivery.
Comparison of the lymphatic transport of radiolabeled 1,3‐dioleoylglycerol and trioleoylglycerol in rats
Authors: Yanagita Teruyoshi , Ikeda Ikuo , Wang Yu‐ming , Nakagiri Hideaki 
Published: November 2006

AbstractIt has been reported that, compared with TAG, DAG suppresses postprandial hypertriacylglycerolemia and reduces visceral fat levels in experimental animals and humans. To clarify the mechanism responsible for these beneficial effects, we compared the lymphatic transport of 1,3‐DAG, a major isomer of DAG, and TAG in rats. Male SD rats, after insertion of a cannula into the thoracic duct, were given 1,3‐di[1‐14C]oleoylglycerol or tri[1‐14C]oleoylglycerol via a stomach tube. The 24‐h receovery of the radioactivity from 1,3‐di[14C]oleoylglycerol in the lymph was slightly but significantly lower than that from tri[14C]oleoylglycerol (81.3±1.0 vs. 86.5±1.2%, respectively). However, in the first 1‐h interval after administration, the recovery of radioactivity from 1,3‐dioleoylglycerol was almost half of that from trioleoylglycerol (17.5±2.0 vs. 31.1±1.4%). The amount of TAG and phospholipids secreted into the lymph was significantly lower 1 h after the administration of 1,3‐dioleoylglycerol compared with that after the administration of trioleoylglycerol. More than 90% of the radioactivity recovered in the lymph in the first 3 h was distributed in the TAG fraction for both 1,3‐dioleoylglycerol and trioleoylglycerol. These results suggest that slower lymphatic transport of 1,3‐DAG compared with TAG could be a factor in the suppression of postprandial hypertriacylglycerolemia. The possibility that the slower lymphatic transport of DAG contributes to the antiobesity action observed in the feeding of 1,3‐DAG cannot be excluded.
Alteration of 20∶5n−3 and 22∶6n−3 fat contents and liver peroxisomal activities in fenofibrate‐treated rainbow trout
Authors: Du Zhen‐yu , Demizieux Laurent , Degrace Pascal , Gresti Joseph , Moindrot Bastien , Liu Yong‐jian , Tian Li‐xia , Cao Jun‐ming , Clouet Pierre 
Published: November 2006

AbstractFish easily accumulate n−3 PUFA of exogenous origin, but the underlying mechanisms are not well established in the whole animal. This study was undertaken to investigate whether this feature was physiologically associated with mitochondrial and peroxisomal capacities that differentially affect FA oxidation. For this purpose, peroxisomal FA oxidation was increased by treating rainbow trout with fenofibrate, which strongly stimulates the peroxisome proliferator‐activated receptor‐α in rodents. Diets containing EPA and DHA, with or without fenofibrate added, were administered to male trout for 12 d. After treatment, neither liver hypertrophy nor accumulation of fat was apparent within the liver and muscle cells. However, fenofibrate treatment decreased the contents of EPA and DHA in the liver, white muscle, and intraperitoneal fat tissue, which represented (per whole body) at least 280 mg less than in controls. Carnitine‐dependent palmitate oxidation rates, expressed per gram of liver, were slightly increased by fenofibrate when measured from tissue homogenates and were unchanged when calculated from isolated mitochondria, relative to control fish. The treatment altered neither carnitine palmitoyltransferase I activity rates, expressed per gram of liver, nor the sensitivity of the enzyme to malonyl‐CoA inhibition, but did increase the malonyl‐CoA content (+45%). Meanwhile, fenofibrate increased (by about 30%) the peroxisome‐related activities, i.e, catalase, carnitine‐independent palmitate oxidation, acyl‐CoA oxidase, and the peroxisomal FA‐oxidizing system, relative to the control group. The data strongly suggest that the induction of peroxisomal activities, some of which being able to oxidize very long chain FA, was responsible for the lower contents of EPA and DHA in the body lipids of fenofibrate‐treated trout.
Effects of EPA and DHA on proliferation, cytokine production, and gene expression in Raji cells
Authors: Verlengia Rozangela , Gorjão Renata , Kanunfre Carla Cristine , Bordin Silvana , de Lima Thais Martins , Martins Edgair Fernandes , Newsholme Philip , Curi Rui 
Published: November 2006

AbstractThe effects of EPA and DHA on the function and gene expression of a B‐lymphocyte cell line (Raji) were investigated. Proliferation; production of interleukin‐10 (IL‐10), tumor necrosis factor (TNF)‐α, and interferon (INF)‐γ; and expression of pleiotropic genes were evaluated. Cell proliferation was increased in the presence of 12.5 μM EPA (approximately twofold) and 12.5 μM DHA (approximately 1.5‐fold). EPA and DHA (25 μM) also decreased production of the key immunoregulatory cytokines IL‐10, TNF‐α, and INF‐γ. EPA and DHA changed the expression of specific genes, but this effect was more marked for EPA (25.9% of genes investigated) compared with DHA (8.4% of genes investigated). EPA and DHA affected the expression of genes clustered as: cytokines, signal transduction, transcription, cell cycle, defense and repair, apoptosis, cell adhesion, cytoskeleton, and hormones. The most remarkable changes were observed in the genes of signal transduction and transcription. These results led us to conclude that the mechanism of DHA and EPA effects on B‐lymphocyte functions includes regulation of gene expression. Thus, the ingestion of fish oil, a rich source of EPA and DHA, may have a strong effect on B‐lymphocyte functionin vivo. However, remarkable differences were observed between DHA and EPA, demonstrating that specific effects of these FA may be responsible for the marked differences in edible oil effects on immune functionin vivoreported by others.
Astonishing diversity of natural surfactants: 1. Glycosides of fatty acids and alcohols
Authors: Dembitsky Valery M. 
Published: November 2006

AbstractAlkyl and fatty acid glycosides have become of great commercial interest in general and specifically for the pharmaceutical, cosmetic, and food industries. Natural surfactants are good sources for future chemical preparation of these glycosides. This review article shows an astonishing diversity of natural surfactants that could be used in laboratories and industry. More than 250 natural surfactants, including their chemical structures and biological activities, are described in this review article.
Dietary modulation of fatty acid profiles and oxidative status of rat hepatocyte nodules: Effect of different n−6/n−3 fatty acid ratios
Authors: Abel S. , De Kock M. , Smuts C. M. , de Villiers C. , Swanevelder S. , Gelderblom W. C. A. 
Published: November 2006

AbstractMale Fischer rats were fed the AIN76A diet containing varying n−6/n−3 FA ratios using sunflower oil (SFO), soybean oil (SOY), and SFO supplemented with EPA‐50 and GLA‐80 (GLA) as fat sources. Hepatocyte nodules, induced using diethylnitrosamine followed by 2‐acetylaminofluorene/partial hepatoctomy promotion, were harvested, with surrounding and respective dietary control tissues, 3 mon after partial hepatectomy. The altered growth pattern of hepatocyte nodules in rats fed SFO is associated with a distinct lipid pattern entailing an increased concentration of PE, resulting in increased levels of 20∶4n−6. In addition, there is an accumulation of 18∶1n−9 and 18∶2n−6 and a decrease in the end products of the n−3 metabolic pathway in PC, suggesting a dysfunctional Δ‐6‐desaturase enzyme. The hepatocyte nodules of the SFO‐fed rats exhibited a significantly reduced lipid peroxidation level that was associated with an increaser in the glutathione (GSH) concentration. The low n−6/n−3 FA ratio diets significantly decreased 20∶4n−6 in PC and PE phospholipid fractions with a concomitant increase in 20∶5n−3, 22∶5n−3, and 22∶6n−3. The resultant changes in the 20∶4/20∶5 FA ratio and the 20∶3n−6 FA level in the case of the GLA diet suggest a reduction of prostaglandin synthesis of the 2‐series. The GLA diet also counteracted the increased level of 20∶4n−6 in PE by equalizing the nodule/surrounding ratio. The low n−6/n−3 ratio diets significantly increased lipid peroxidation levels in hepatocyte nodules, mimicking the level in the surrounding and control tissue while GSH was decreased. An increase in n−3 FA levels and oxidative status resulted in a reduction in the number of glutathione‐S‐transferase positive foci in the liver of the GLA‐fed rats. Modulation of cancer development with low n−6/n−3 ratio diets containing specific dietary FA could be a promising tool in cancer intervention in the liver.
Rapid clearance of hexachlorobenzene from chylomicrons
Authors: Jandacek Ronald J. , Zheng Shuqin , Yang Qing , Iso Patrick 
Published: November 2006

AbstractToxic organochlorines that are present in food are lipophilic and carried by chylomicrons. We have studied the clearance of an organochlorine, hexachlorobenzene, from chylomicrons. Chylomicrons were obtained from mesenteric lymph of rats that were intraduodenally given 14C‐hexachlorobenzene and 3H‐triolein. The labeled chylomicrons were injected intravenously into recipient rats, and the clearance of isotopes was followed. Surprisingly, the hexachlorobenzene disappeared from the plasma more rapidly than the triolein. This unexpected result raises questions about the manner in which hexachlorobenzene is delivered to tissues. The tissue distribution of the hexachlorobenzene is consistent with its rapid uptake.
Separation of vitamin E (tocopherol, tocotrienol, and tocomonoenol) in palm oil
Authors: Ng Mei Han , Choo Yuen May , Ma Ah Ngan , Chuah Cheng Hock , Hashim Mohd Ali 
Published: November 2006

AbstractPrevious reports showed that vitamin E in palm oil consists of various isomers of tocopherols and tocotrienols [α‐tocopherol (α−T), α‐tocotrienol, γ‐tocopherol, γ‐tocotrienol, and δ‐tocotrienol), and this is normally analyzed using silica column HPLC with fluorescence detection. In this study, an HPLC‐fluorescence method using a C30 silica stationary phase was developed to separate and analyze the vitamin E isomers present in palm oil. In addition, an α‐tocomonoenol (α−T1) isomer was quantified and characterized by MS and NMR. α−T1 constitutes about 3–4% (40±5 ppm) of vitamin E in crude palm oil (CPO) and is found in the phytonutrient concentrate (350±10 ppm) from palm oil, whereas its concentration in palm fiber oil (PFO) is about 11% (430±6 ppm). The relative content of each individual vitamin E isomer before and after interesterification/transesterification of CPO to CPO methyl esters, followed by vacuum distillation of CPO methyl esters to yield the residue, remained the same except for α−T and γ−T3. Whereas α−T constitutes about 36% of the total vitamin E in CPO, it is present at a level of 10% in the phytonutrient concentrate. On the other hand, the composition of γ−T3 increases from 31% in CPO to 60% in the phytonutrient concentrate. Vitamin is present at 1160±43 ppm, and its concentrations in PFO and the phytonutrient concentrate are 4,040±41 and 13,780±65 ppm, respectively. The separation and quantification of α−T1 in palm oil will lead to more in‐depth knowledge of the occurrence of vitamin E in palm oil.
Olive oil and modulation of cell signaling in disease prevention
Authors: Wahle Klaus W. J. , Caruso Donatella , Ochoa Julio J. , Quiles Jose L. 
Published: November 2006

AbstractEpidemiological studies show that populations consuming a predominantly plant‐based Mediterranean‐style diet exhibit lower incidences of chronic diseases than those eating a northern European or North American diet. This observation has been attributed to the greater consumption of fruits and vegetables and the lower consumption of animal products, particularly fat. Although total fat intake in Mediterranean populations can be higher than in other regions (ca. 40% of calories), the greater proportion is derived from olive oil and not animals. Increased olive oil consumption is implicated in a reduction in cardiovascular disease, rheumatoid arthritis, and, to a lesser extent, a variety of cancers. Olive oil intake also has been shown to modulate immune function, particularly the inflammatory processes associated with the immune system. Olive oil is a nonoxidative dietary component, and the attenuation of the in‐flammatory process it elicits could explain its beneficial effects on disease risk since oxidative and inflammatory stresses appear to be underlying factors in the etiology of these diseases in man. The antioxidant effects of olive oil are probably due to a combination of its high oleic acid content (low oxidation potential compared with linoleic acid) and its content of a variety of plant antioxidants, particularly oleuropein, hydroxytyrosol, and tyrosol. It is also possible that the high oleic acid content and a proportionate reduction in linoleic acid intake would allow a greater conversion of α‐linolenic acid (18∶3n−3) to longer‐chain n−3 PUFA, which have characteristic health benefits. Adoption of a Mediterranean diet could confer health benefits in high‐risk populations.
Functional alterations in NO, PGI2 and EDHF pathways in the aortic endothelium after myocardial infarction in rats
Authors: Csanyi Gabor , Bauer Michael , Dietl Wolfgang , Lomnicka Magdalena , Stepuro Tatiana , Podesser Bruno K. , Chlopicki Stefan 
Published: November 2006

AbstractBackgroundPrevious work on endothelial dysfunction in post‐MI heart failure has shown conflicting results.AimTo analyze gender related alterations in NO‐, PGI2‐ and EDHF‐dependent endothelial function in the thoracic aorta 7 and 42 days after myocardial infarction (MI).Methods and resultsMI was induced by coronary artery ligation in female and male Sprague–Dawley rats. There was no gender related difference in infarct‐size or in the impairment of fractional shortening of the left ventricle 42 days after coronary ligation. Neither acetylcholine‐induced (Ach) vasodilation nor basal PGI2 production in the aorta was modified by coronary ligation. Interestingly, 7 days after MI, basal NO production was impaired and the EDHF component of Ach‐induced vasodilation was up‐regulated, in both male and female rats. However, 42 days post‐MI, basal NO was only impaired in male rats, while EDHF was only up‐regulated in female rats.ConclusionMI induced impairment of functional activity of basal NO production and adaptive up‐regulation of the EDHF component of Ach‐induced relaxation. The above alterations in endothelial function in the aorta were gender‐specific at 42 days but not 7 days after MI. Some of the previously reported discrepancies in the development of endothelial dysfunction in the post‐MI period may be gender related differences.
Screening Extremophiles for Bioconversion Potentials
Authors: Kim Jin‐Woo , Peeples Tonya L. 
Published: November 2006

AbstractA screening protocol was developed and implemented to evaluate extremophiles, in particular hyperthermophiles and thermoacidophiles, for their capacity to transform starch‐based feedstocks to high‐value organic acids and solvents. Screening results of 14 extremophiles showed promising growth and biotransformation potentials. In particular, Hyperthermus butylicus, Thermococcus litoralis, and Sulfolobus acidocaldarius were identified as producers of both organic acids and solvents under the screening protocol. The screening effort presented here represents an important step toward realization of biotransformation potentials of extremophiles, potentially improving upon biomass‐based processes.
Dihydrodipicolinate synthase from Thermotoga maritima
Authors: Pearce F. Grant , Perugini Matthew A. , Mckerchar Hannah J. , Gerrard Juliet A. 
Published: November 2006

DHDPS (dihydrodipicolinate synthase) catalyses the branch point in lysine biosynthesis in bacteria and plants and is feedback inhibited by lysine. DHDPS from the thermophilic bacterium Thermotoga maritima shows a high level of heat and chemical stability. When incubated at 90 °C or in 8 M urea, the enzyme showed little or no loss of activity, unlike the Escherichia coli enzyme. The active site is very similar to that of the E. coli enzyme, and at mesophilic temperatures the two enzymes have similar kinetic constants. Like other forms of the enzyme, T. maritima DHDPS is a tetramer in solution, with a sedimentation coefficient of 7.2 S and molar mass of 133 kDa. However, the residues involved in the interface between different subunits in the tetramer differ from those of E. coli and include two cysteine residues poised to form a disulfide bond. Thus the increased heat and chemical stability of the T. maritima DHDPS enzyme is, at least in part, explained by an increased number of inter-subunit contacts. Unlike the plant or E. coli enzyme, the thermophilic DHDPS enzyme is not inhibited by (S)-lysine, suggesting that feedback control of the lysine biosynthetic pathway evolved later in the bacterial lineage.
Pyrrolidine dithiocarbamate protects the small bowel from warm ischaemia/reperfusion injury of the intestine: the role of haem oxygenase
Authors: Mallick Ismail H. , Winslet Marc C. , Seifalian Alexander M. 
Published: November 2006

IR (ischaemia/reperfusion) injury of the intestine occurs commonly during abdominal surgery. We have previously shown that PDTC (pyrrolidine dithiocarbamate), an HO-1 (haem oxygenase-1) donor, improves intestinal microvascular perfusion. In the present study, we have investigated the effects of PDTC on the intestinal microcirculation following IR (ischaemia/reperfusion) injury of the intestine. Male Sprague–Dawley rats (n=72) were randomly assigned to four groups (n=18/group): (i) sham-operated group, who underwent laparotomy without induction of IR of the intestine; (ii) IR group, who were subjected to 30 min of superior mesenteric artery occlusion and 2 h of reperfusion; (iii) PDTC+IR group, who received PDTC prior to IR; and (iv) ZnPP group, who received the HO-1 inhibitor ZnPP (zinc protoporphyrin) followed by procedures as in group (iii). The ileum was evaluated for changes in tissue cytochrome c oxidase redox status, RBC (red blood cell) dynamics and leucocyte–endothelial interactions. The expression of HO-1 in the ileal tissue was examined at the end of the reperfusion. PDTC significantly improved the intestinal tissue oxygenation, mucosal perfusion index and RBC velocity compared with the IR and ZnPP groups. PDTC also decreased the leucocyte–endothelial interactions (P&lt;0.05 compared with the IR and ZnPP groups). PDTC induced the expression of HO-1, whereas ZnPP abolished this effect.
Effects of adrenomedullin on acute ischaemia-induced collateral development and mobilization of bone-marrow-derived cells
Authors: Abe Minami , Sata Masataka , Suzuki Etsu , Takeda Ryo , Takahashi Masao , Nishimatsu Hiroaki , Nagata Daisuke , Kangawa Kenji , Matsuo Hisayuki , Nagai Ryozo , Hirata Yasunobu 
Published: November 2006

Adrenomedullin exerts not only vasodilatory effects, but also angiogenic effects. In the present study, we investigated the effects of adrenomedullin on collateral formation and circulating bone-marrow-derived cells after acute tissue ischaemia. Bone marrow of 8–10-week-old female C57BL/6J mice was replaced with that from GFP (green fluorescent protein) transgenic mice (GFP mice). At 8 weeks after transplantation, hindlimb ischaemia was induced by resecting the right femoral artery and a plasmid expressing human adrenomedullin (50 μg) was injected into the ischaemic muscle, followed by in vivo electroporation on a weekly basis. Overexpression of adrenomedullin significantly enhanced the blood flow recovery compared with controls (blood flow ratio, 1.0±0.2 compared with 0.6±0.3 respectively, at week 4; P&lt;0.05) and increased capillary density in the ischaemic leg as determined by anti-CD31 immunostaining of the ischaemic muscle (567±40 compared with 338±65 capillaries/mm2 respectively, at week 5; P&lt;0.05). There were more GFP-positive cells in the thigh muscle of the mice injected with adrenomedullin than in that of the control mice (29.6±4.5 compared with 16.5±3.3 capillaries/mm2 respectively, at week 5; P&lt;0.05). We repeated the same experiments using LacZ-knock-in mice instead of GFP mice, and obtained similar results. These findings suggest that adrenomedullin may augment ischaemia-induced collateral formation with some effects on circulating bone-marrow-derived cells.