bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of 6‐hydroxy δ‐lactones and 5,6‐dihydroxy eicosanoic/docosanoic acids from meadowfoam fatty acids via a lipase‐mediated self‐epoxidation
Authors: Frykman Hans B. , Isbell Terry A. 
Published: May 2007

AbstractMeadowfoam fatty acids were reacted with hydrogen peroxide in a lipase‐catalyzed autocatalytic system, forming a mixture of 5,6‐epoxyeicosanoic, 13,14‐epoxydocosanoic, 5,6‐epoxydocosanoic, and 5,6‐13,14‐diepoxydocosanoic acids in 98% yield. The 5,6‐epoxy acids were cyclized to 6‐hydroxy δ‐eicosanoic/docosanoic lactones by sulfuric acid catalysis in high yield (99%). 5,6‐Dihydroxy acids could be obtained from 6‐hydroxy δ‐lactones by a simple alkaline work‐up procedure. Meadowfoam fatty acids were converted (77% yield) in a one‐pot reaction to 6‐hydroxy δ‐lactones by in situ performic acid epoxidation and subsequent addition of sulfuric acid.
Identification of cyclopentenyl fatty acids by1H and13C nuclear magnetic resonance
Authors: Blaise Pierre , Farines Marie , Soulier Jacques 
Published: May 2007

AbstractGorlic, chaulmoogric and hydnocarpic fatty acids, specific to the seed oil of the genusHydnocarpussp. (Flacourtiaceae), are determined only with difficulty by gas chromatography. These fatty acids were isolated in their methyl ester form by a combination of different chromatographic techniques (thin‐layer chromatography/Ag+and high‐pressure liquid chromatography). The proton and carbon nuclear magnetic resonance analysis of these fatty acid methyl esters showed some characteristic signals of the cyclopentenyl ring. The presence of these signals in the proton and/or carbon nuclear magnetic resonance spectrum of an oil thus will allow us to confirm the presence of these cyclopentenyl fatty acids in lipids.
Antioxidant efficacy of methanolic extracts of peanut hulls in soybean and peanut oils
Authors: Duh Pin‐Der , Yen Gow‐Chin 
Published: May 2007

AbstractAntioxidant activity of methanolic extracts of peanut hulls (MEPH) was evaluated in soybean and peanut oils after accelerated oxidation at 60°C. Results showed that the oils with 0.12, 0.48, and 1.20% MEPH had significantly (P<0.05) lower peroxide values and acid values than the control after storage at 60°C. Moreover, oils with 0.48 and 1.20% MEPH were significantly (P<0.05) superior to 0.02% butylated hydroxyanisole (BHA) in reducing oxidation of both oils. Negative synergism was observed when 0.48 and 1.20% MEPH were mixed with 0.01% dl‐α‐tocopherol or 0.01% BHA in soybean oil compared to MEPH alone.
Experimental characterization of emulsion formation and coalescence by nuclear magnetic resonance restricted diffusion techniques
Authors: Lee H.‐Y. , McCarthy M. J. , Dungan S. R. 
Published: May 2007

AbstractNuclear magnetic resonance (NMR) is explored as a technique for noninvasively monitoring emulsion droplet formation and destabilization. The method makes use of the fact that the diffusion of oil molecules within oil‐in‐water emulsion droplets results in attenuation of a coherent magnetic signal that emanates from those molecules. If oil diffusion is limited by the size of the droplet, the shape of a plot of attenuation over time is directly affected by the droplet radius. We use this approach to determine noninvasively the effect of surfactant type, surfactant concentration, pH, and ionic strength on droplet sizes within a 40 wt% octane and water emulsion, stabilized by Tween 20 or β‐lactoglobulin (β‐Lg). We find that addition of the low‐molecular‐weight Tween 20 forms finer emulsion droplets than does addition of the protein, and that the Tween 20 emulsion is sensitive to surfactant concentration below a threshold “saturation” concentration. The droplet sizes in β‐Lg‐containing emulsions increase as pH increases above the isoelectric point and as ionic strength increases. The fact that the NMR technique does not mistake clusters of droplets for single large droplets makes the analysis of these effects unambiguous. We further extend the use of NMR diffusion techniques to monitor the effect of surfactant type, surfactant concentration, and convection on the rate of droplet coalescence. The ability of NMR methods to distinguish between large single droplets and droplet clusters makes it well‐suited to monitor coalescence processes independently from flocculation.
Lipid and fatty acid biosynthesis by Rhodotorula minuta
Authors: Saxena Vani , Sharma C. D. , Bhagat S. D. , Saini V. S. , Adhikari D. K. 
Published: May 2007

AbstractDemand for fatty acids is increasing at an annual rate of 17%, due to their increased use in the oleochemical and transport industries. Presently, vegetable oils are the major source of fatty acids, whereas lipids with fatty acids similar to those of some vegetable oils have been reported to be synthesized by oleaginous microorganisms. In the present study, the culturing conditions for the oleaginous yeast Rhodotorula minuta IIP‐33 have been optimized. In contrast to the lipid accumulation characteristics of most oleaginous yeasts, a carbon‐to‐nitrogen ratio of 30 was favorable for maximal accumulation of lipids (48%) with 22.5% conversion of glucose as carbon substrate. The lipids contained fatty acids in the C7–C18 range, the relative composition of which varied with culture temperature.
In Vitro hydrolysis of fungal oils: Distribution of arachidonic acid‐containing triacylglycerol molecular species
Authors: Liu Jim‐Wen , Bobik Emi G. , Huang Yung‐Sheng 
Published: May 2007

AbstractFour commercially prepared arachidonic acidrich oils from the fungus Mortierella alpina were analyzed by high‐performance liquid chromatography and gas chromatography. The levels of arachidonic acid and the distribution of triacylglycerol (TG) molecular species varied significantly among these oils. The major arachidonate‐containing TG species were AAA, LAA, DAA, OAA, PAA, SAA, OLA, PGA, PLA, POA, and SOA where the abbreviations A, D, G, L, O, P, and S represent arachidonic (20:4n‐6), dihomo‐γ‐linolenic (20:3n‐6), γ‐linolenic (18:3n‐6), linoleic (18:2n‐6), oleic (18:1n‐9), palmitic (16:0), and stearic (18:0) acids, respectively. In vitro incubation of the TG fractions, purified from these oils with porcine pancreatic lipase for 5 min, yields a mixture of intermediate products, such as 1,2‐ and 2,3‐diacylglycerols (1,2‐ and 2,3‐DG), 2‐monoacylglycerol (2‐MG) and free fatty acids (FFA), as well as residual TG. The degrees of hydrolysis varied significantly among the four oil preparations, ranging from 35 to 57%. The levels of arachidonic acid in the residual TG and 1,2(2,3)‐DG were significantly higher than those in the original TG, whereas those in the FFA fraction were significantly lower than those in 1,2(2,3)‐DG and 2‐MG. Results from this study suggest that the bioavailability of arachidonic acid differs among fungal oils prepared by different suppliers. These differences could be attributed to the arachidonic acid content of the oil as well as to the association of arachidonic acid with other fatty acids in the same TG molecule.
Screening catalytic lipase activities with an analytical supercritical fluid extractor
Authors: Frykman Hans B. , Snyder Janet M. , King Jerry W. 
Published: May 2007

AbstractTwo different screenings of several commercial lipases were performed to find a lipase with superior performance for the conversion of lipid moieties to their fatty acid methyl ester (FAME) derivatives under supercritical conditions. The first screening was done under hydrolytic conditions in a buffer. The second screening was done under supercritical conditions with CO2, utilizing some of the same lipases for the methanolysis of different lipids. For the substrates studied, there was a significant difference in lipase activity under the two above conditions. Significant hydrolytic activity was demonstrated for three different lipid types (triglycerides, sterols, and phospholipids) with Lipase PS30, but when the same lipase was immobilized on an Accurel carrier (polypropylene), the activity decreased considerably. The opposite was found for Lipase G, which showed strong activity when immobilized and under supercritical conditions. Furthermore, Chirozyme L‐1 was superior under supercritical conditions. The altered substrate specificity that some of these lipases show in supercritical CO2 suggests several interesting synthetic options and applications under these conditions.
Functionalization at the double‐bond region of jojoba oil. 9. solid‐state nuclear magnetic resonance characterization of substituted jojoba wax chemically bonded to a polystyrene matrix
Authors: Binman Sofia , Vega Shimon , Belfer Sofia , Shani Arnon 
Published: May 2007

AbstractSolid extractants for metal ions have been prepared by chemical bonding of jojoba wax to a polystyrene backbone, followed by phosphonation or sulfur‐chlorination of the jojoba moiety. In this study, the intermediates and final solid products of the reactions were characterized by solid‐state 13C and 31P nuclear magnetic resonance spectroscopy. The spectra showed the expected chemical shifts of the atoms involved in the chemical reactions, as well as other parts of the reacting molecules. Thus, the carbonyl carbon of the jojoba chain appears at 175 ppm, the methyl carbons at 15 ppm, the polystyrene backbone at 40–42 ppm (aliphatic carbons) and 128, 137, 143–147 (aromatic carbons). Carbons adjacent to N, S, and P appear at 45–55, 60, and 48 ppm, respectively.
Remarks on official methods employing boron trifluoride in the preparation of methyl esters of the fatty acids of fish oils
Authors: Ackman R. G. 
Published: May 2007

AbstractSome “official methods” for preparing methyl esters of the fatty acids from oils or fats may be referred to by users as the boron trifluoride (BF3) method and invariably have two stages. The first stage, brief treatment with alkali [commonly NaOH in methanol (MeOH), sometimes NaOCH3] and heat has been popularly described as a saponification step for over 30 yr. In fact, the disappearance of visible fat or oil is mostly transesterification, which can be accomplished in a few minutes under mild conditions. Free fatty acids (FFA) originally present, or produced by saponification, are not converted to methyl esters at this stage. The second stage, heating in BF3‐MeOH, has in practice been as short as 2 min. It can convert all FFA to methyl esters, but this step requires at least 30 min. Examples from the recent literature illustrate the necessity of extending the time for BF3‐MeOH transesterification of lipids or oils and methylation of FFA. No alkali transesterification is needed.
Naturalistic follow-up of co-morbid substance use in schizophrenia: the West London first-episode study
Authors: Harrison I. , Joyce E. M. , Mutsatsa S. H. , Hutton S. B. , Huddy V. , Kapasi M. , Barnes T. R. E. 
Published: May 2007

BackgroundThe impact of co-morbid substance use in first-episode schizophrenia has not been fully explored.MethodThis naturalistic follow-up of a cohort of 152 people with first-episode schizophrenia examined substance use and clinical outcome in terms of symptoms and social and neuropsychological function.ResultsData were collected on 85 (56%) of the patient cohort after a median period of 14 months. Over the follow-up period, the proportion of smokers rose from 60% at baseline to 64%. While 30% reported lifetime problem drinking of alcohol at baseline, only 15% had problem drinking at follow-up. Furthermore, while at baseline 63% reported lifetime cannabis use and 32% were currently using the drug, by the follow-up assessment the latter figure had fallen to 18.5%. At follow-up, persistent substance users had significantly more severe positive and depressive symptoms and greater overall severity of illness. A report of no lifetime substance use at baseline was associated with greater improvement in spatial working memory (SWM) at follow-up.ConclusionsPast substance use may impede recovery of SWM performance in people with schizophrenia in the year or so following first presentation to psychiatric services. The prevalence of substance use other than tobacco tends to diminish over this period, in the absence of specific interventions. Persistent substance use in first-episode schizophrenia is associated with more severe positive and depressive symptoms but not negative symptoms, and should be a target for specific treatment intervention.
Population status and distribution of Taita White-eye Zosterops silvanus in the fragmented forests of Taita Hills and Mount Kasigau, Kenya
Authors: Mulwa Ronald K , Bennun Leon A , Ogol Callistus K. P. O. , Lens Luc 
Published: May 2007

AbstractOur study focused on the Taita White-eye Zosterops silvanus, one of three bird species endemic to the Taita Hill forests, south-east Kenya. Formerly considered Critically Endangered, Taita White-eye has been down-listed to Endangered following the findings of this study. Between November 1998 and September 1999 we counted this species along line transects to establish their current population status and distribution in its entire range. White-eye censuses were conducted in nine forest fragments of the Taita Hills and the virtually undisturbed Mt Kasigau forest. The total global population of Taita White-eyes was estimated to be c. 7,100 birds. Mt Kasigau was shown to be the species' main stronghold, maintaining a very high density (26 birds ha−1) and holding 80% (5,600 individuals) of the entire population. In the Taita Hills forests, densities were consistently higher in the small isolated fragments than in the large ones, though the former held only a small population (3% of total). At Mt Sagala, a large isolated block where indigenous trees have been largely replaced with exotic plantation, this species was not encountered. We found no evidence of interchange between the White-eye populations on Mt Kasigau and the Taita Hills forests, probably because of the separation by a low-altitude, dry woodland habitat barrier. While prioritization for conservation action should focus more on the Taita Hills forest fragments, Mt Kasigau should be treated as fragile ecosystem which holds a huge, apparently insular population of Taita White-eyes.
Conservation Status of the Chilean Woodstar Eulidia yarrellii
Authors: Estades Cristián F. , Aguirre Juan , Escobar Martín A. H. , Tomasevic Jorge A. , Vukasovic María Angélica , Tala Charif 
Published: May 2007

AbstractWe assessed the conservation status of the Chilean Woodstar Eulidia yarrellii, a small hummingbird endemic to a few desert valleys of northern Chile and southern Peru. Although no population studies had been conducted, this rare species was presumed to have undergone a severe population decline during the past decades. Fieldwork in Chile produced a population estimate for September 2003 of 1,539 individuals (929–2,287; 90% CI), located in just two valleys: Azapa and Vitor. There was no evidence of stable populations elsewhere. Our observations tend to confirm the hypothesis of a past decline and evidence points to three main factors driving that trend: (1) Most natural habitat has disappeared and the species relies mostly on artificial resources for feeding and nesting. (2) The start of heavy use of pesticides in the Azapa valley in the 1960s in order to control the Mediterranean fruit fly and other crop pests coincides with the last reports describing the species as abundant. (3) The irruption in the last two decades of the Peruvian Sheartail Thaumastura cora has apparently exerted serious competition pressure on the species. These findings support the classification of the species as globally Endangered. We describe the main lines of action of the recently approved Recovery Plan for the Chilean Woodstar.
Mutations at F637 in the NMDA receptor NR2A subunit M3 domain influence agonist potency, ion channel gating and alcohol action
Authors: Ren H , Salous A K , Paul J M , Lipsky R H , Peoples R W 
Published: May 2007

Background and purpose:NMDA receptors are important molecular targets of ethanol action in the CNS. Previous studies have identified a site in membrane‐associated domain 3 (M3) of the NR1 subunit and two sites in M4 of the NR2A subunit that influence alcohol action; the sites in NR2A M4 also regulate ion channel gating. The purpose of this study was to determine whether mutations at the site in the NR2A subunit corresponding to the NR1 M3 site influence alcohol action and ion channel gating.Experimental approach:We investigated the effects of mutations at phenylalanine (F) 637 of the NR2A subunit using whole‐cell and single‐channel patch‐clamp electrophysiological recording in transiently‐transfected HEK 293 cells.Key results:Mutations at F637 in the NR2A subunit altered peak and steady‐state glutamate EC50 values, maximal steady‐state to peak current ratios (Iss:Ip), mean open time, and ethanol IC50 values. Differences in glutamate potency among the mutants were not due to changes in desensitization. Ethanol IC50 values were significantly correlated with glutamate EC50 values, but not with maximal Iss:Ip or mean open time. Ethanol IC50 values were linearly and inversely related to molecular volume of the substituent.Conclusions and implications:These results demonstrate that NR2A(F637) influences NMDA receptor affinity, ion channel gating, and ethanol sensitivity. The changes in NMDA receptor affinity are likely to be the result of altered ion channel gating. In contrast to the cognate site in the NR1 subunit, the action of ethanol does not appear to involve occupation of a critical volume at NR2A(F637).British Journal of Pharmacology (2007) 151, 749–757; doi:10.1038/sj.bjp.0707254
Taking the sting out of pain
Authors: Nagy I , Paule C , White J , Urban L 
Published: May 2007

While the role of the brain kallikrein‐kinin system in the development of various pathological processes, such as oedema formation following brain injury or induction of central hypertonia has generated major interest, the possible role of this system in nociceptive processing has received little attention. In their present paper, Mortari et al. (2007) show that bradykinin B2 receptor activation in the brain by the bradykinin analogue, Thr6‐bradykinin, isolated from the venom of the social wasp, Polybia occidentalis potently reduces acute, noxious heat‐evoked reflex responses in naive rats. The unknown underlying mechanism of this powerful antinociceptive effect reminds us that the supraspinal antinociceptive system is still a “black box” in many aspects and awaits thorough investigation.British Journal of Pharmacology (2007) 151, 721–722; doi:10.1038/sj.bjp.0707274
K+ channel modulation of slow wave activity in the guinea‐pig prostate
Authors: Nguyen D‐T T , Lang R J , Exintaris B 
Published: May 2007

Background and purpose:The aim of this study was to investigate the role of different K+ channel populations and the inhibitory effect of various exogenously applied K+ channel openers in the regulation of slow wave activity in the guinea‐pig prostate.Experimental approach:Recordings of membrane potential were made using intracellular microelectrodes.Key results:Tetraethylammonium (TEA 300 μM and 1 mM), iberiotoxin (150 nM) and 4‐aminopyridine (4‐AP 1 mM) increased the frequency of slow wave discharge. Apamin (1–200 nM) and glibenclamide (1 μM) had no effect on slow wave activity. Lemakalim (1 μM) and PCO‐400 (1 μM) abolished the slow waves, as did sodium nitroprusside (SNP 10 μM) and calcitonin gene‐related peptide (CGRP 100 nM). The inhibitory effect of these agents was independent of a significant change in membrane potential. In the presence of 4‐AP (1 mM), TEA (1 mM) or glibenclamide (1 μM) the inhibitory actions of SNP (10 μM) were attenuated. The inhibitory actions of CGRP (100 nM) were also reversed by glibenclamide (1 μM). In contrast, isoprenaline (1 μM) did not alter the frequency of slow wave discharge.Conclusions and implications:These results demonstrate that BKCa and 4‐AP‐sensitive K+ channels regulate the frequency of prostatic slow wave discharge. SNP and CGRP abolish slow waves in a hyperpolarisation‐independent manner, partially via opening of KATP channels. BKCa and 4‐AP‐sensitive K+ channels also play an important role in the SNP‐induced inhibition of slow wave activity. The lack of membrane hyperpolarisation associated with the SNP‐ and CGRP‐induced inhibition implies that the channels involved in this action are not predominantly located on the smooth muscle cells.British Journal of Pharmacology (2007) 151, 828–836; doi:10.1038/sj.bjp.0707283
Mitochondrial Medicine: Pharmacological targeting of mitochondria in disease
Authors: Armstrong J S 
Published: May 2007

Mitochondria play a central role in cell life and death and are known to be important in a wide range of diseases including the cancer, diabetes, cardiovascular disease, and the age‐related neurodegenerative diseases. The unique structural and functional characteristics of mitochondria enable the selective targeting of drugs designed to modulate the function of this organelle for therapeutic gain. This review discusses mitochondrial drug targeting strategies and a variety of novel mitochondrial drug targets including the electron transport chain, mitochondrial permeability transition, Bcl‐2 family proteins and mitochondrial DNA. Mitochondrial drug‐targeting strategies will open up avenues for manipulating mitochondrial functions and allow for selective protection or eradication of cells for therapeutic gain in a variety of diseases.British Journal of Pharmacology (2007) 151, 1154–1165; doi:10.1038/sj.bjp.0707288
Blockade of MCH1 receptor signalling ameliorates obesity and related hepatic steatosis in ovariectomized mice
Authors: Gomori A , Ishihara A , Ito M , Matsushita H , Ito M , Mashiko S , Iwaasa H , Matsuda M , Bednarek M A , Qian S , MacNeil D J , Kanatani A 
Published: May 2007

Background and purpose:Melanin‐concentrating hormone (MCH) is a cyclic orexigenic neuropeptide predominantly expressed in the lateral hypothalamus. We investigated the roles of MCH1 receptor signalling in ovariectomy (OVX)‐induced obesity in female C57BL/6J mice, an animal model of postmenopausal obesity.Experimental approach:The effects of blocking signalling via the MCH1 receptor on OVX‐induced obesity was investigated by using Mch1r deficient (KO) mice and chronic treatment with a selective MCH1 receptor antagonist.Key results:OVX induced body weight gain and increases in the weight of visceral fat and of liver; these effects were attenuated following OVX in Mch1r KO mice. OVX‐induced triglyceride (TG) accumulation and elevated expression of lipogenic genes were significantly ameliorated in the liver of Mch1r KO mice. In agreement with these results, chronic i.c.v. infusion of a selective MCH1 receptor antagonist significantly reduced body weight gain, visceral fat and liver weights in OVX mice, and hepatic TG contents and lipogenic gene expression levels were normalized.Conclusion and implications:Our results indicate that MCH1 receptor signalling is involved in the development of fatty liver, as well as obesity, in OVX mice, and suggest a therapeutic potential for MCH1 receptor antagonists in the treatment of obesity and fatty liver.British Journal of Pharmacology (2007) 151, 900–908; doi:10.1038/sj.bjp.0707292