bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stereospecific analysis of triacylglycerols rich in long‐chain polyunsaturated fatty acids
Authors: Myher J. J. , Kuksis A. , Geher K. , Park P. W. , Diersen‐Schade D. A. 
Published: November 2006

AbstractSix oils of marine, algal, and microbial origin were analyzed for stereospecific distribution of component fatty acids. The general procedure involved preparation ofsn‐1,2‐(2,3)‐diacylglycerols by partial deacylation with ethylmagnesium bromide or pancreatic lipase, separation of X‐1,3‐ andsn‐1,2(2,3)‐diacylglycerols by borate thin‐layer chromatography, resolution of thesn‐1,2‐ andsn‐2,3‐enantiomers by chiral phase high‐performance liquid chromatography following preparation of dinitrophenylurethane derivatives, and determination of the fatty acid composition by gas chromatography. Unexpected complications arose during a stereospecific analysis of triacylglycerols containing over 33% of either 20∶4 or 22∶6 fatty acids. Thesn‐1,2(2,3)‐diacylglycerols made up of two long‐chain polyunsaturated acids migrated with the X‐1,3‐diacylglycerols and required separate chiral phase resolution. Furthermore, the enzymatic method yieldedsn‐1,2(2,3)‐diacylglycerols, overrepresenting the polyenoic species due to their relative resistance to lipolysis, but prolonged digestion yielded correct composition for the 2‐monoacylglycerols. The final positional distribution of the fatty acids was established by pooling and normalizing the data from subfractions obtained by norman‐ and chiral‐phase separation of diacylglycerols. The molecular species of X‐1,3‐,sn‐1,2‐ andsn‐2,3‐diacylglycerol dinitrophenylurethanes were identified by chiral‐phase liquid chromatography/mass spectrometry with electrospray ionization, which demonstrated a preferential association of the paired long‐chain acids with thesn‐1,2‐ andsn‐2,3‐diacylglycerol isomers.
Platelet and aorta arachidonic and eicosapentaenoic acid levels andin vitro eicosanoid production in rats fed high‐fat diets
Authors: Sanigorski Andrew J. , Sinclair Andrew J. , Hamazaki Tomohito 
Published: November 2006

AbstractThere is a significant interest in the interrelationship between long‐chain n‐3, and n‐6 fatty acids due to their ability to modulate eicosanoid production. In general, the intake of arachidonic acid (AA) results in enhanced eicosanoid production, whereas n‐3 polyunsaturated fatty acids (PUFA) decrease the production of eicosanoids from AA. The purpose of this study was to investigate whether the effects of dietary AA on eicosanoid production in the rat were correlated with the AA and EPA levels in platelets and aorta (eicosanoid‐producing tissues). Four groups of male Sprague‐Dawley rats were fed a highfat diet enriched with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (approximately 100 mg/day of EPA+DHA) for 24 d. During the last 10 d, the four groups were orally supplemented with 0,30,60, and 90 mg/day of ethyl arachidonate. A further group of rats was fed a control diet (without longchain n‐3 PUFA) for 24 d.In vitro aorta prostacyclin (PGI2) production, serum thromboxane A2 (TxA2) production and plasma, and platelet and aorta phospholipid (PL) fatty acids were measured. Enriching the diet with n‐3 PUFA resulted in significant reductions in tissue AA levels and an increase in the n‐3 PUFA, particularly EPA. On this diet, the AA to EPA ratio was 1:1 in platelet PL, and it was 2:1 in the aorta PL. There were significant decreases in thein vitro PGI2 and TxA2 production compared with the control animals. The inclusion of AA in the diet resulted in marked increases in AA levels in the platelet and aorta PL with corresponding decreases in EPA. The lowest dose of AA (30 mg/rat) reversed the effects of 100 mg/day of n‐3 PUFA on AA levels in platelet and aortic PL and onin vitro aorta PGI2 and serum TxA2 production. The dietary AA caused a differential (twofold) increase in TxA2 relative to PGI2 for all three levels of AA supplementation. There were greater changes in the levels of AA and/or EPA in platelet PL compared with the aorta PL, which might have accounted for the differential effects of these PUFA on thromboxane production compared with PGI2 production in this study.
Differential alterations of ethanolamine and choline phosphoglyceride metabolism by clofibrate and retinoic acid in human fibroblasts are not mediated by phorbol ester‐sensitive protein kinase C
Authors: Mandla Suzan G. , Byers David M. , Ridgway Neale D. , Cook Harold W. 
Published: November 2006

AbstractPeroxisomal proliferators and retinoids have been reported to interact to regulate lipid metabolism, particularly β‐oxidation of fatty acids. Based on postulated interactions of these agents at the levels of receptors and response elements, we examined whether interactions exist between the peroxisomal proliferator, clofibrate (CLF), and retinoic acid (RA) in modulation of phospholipid turnover in cultured human skin fibroblasts. Treatment of cultured cells with either 25 μM CLF or 1 μM RA alone decreased [14C]ethanolamine incorporation into ethanolamine phosphoglycerides (EPG) by 20–30%, and simultaneous exposure to both agents resulted in additive inhibition. By contrast, [3H]choline incorporation into phospholipid was stimulated 5–30% by incubation with either agent; when CLF and RA were administered together, the stimulatory effects were additive. Different types of pulse‐chase studies examining effects on uptake, biosynthesis, and degradation of labelled phospholipids indicated stimulation of EPG degradation and inhibition of phosphatidylcholine degradation by CLF; no effect on catabolism of either phospholipid was observed with RA. Combinations of modifiers of protein kinase activity [4β‐12‐O‐tetradecanoylphorbol‐13‐acetate (β‐TPA), 1‐(5‐isoquino‐linesulfonyl)‐2‐methylpiperazine dihydrochloride,N‐(2′‐guanidinoethyl)‐5‐isoquinolinesulfonamide hydrochloride,bis‐indolylmaleimide, staurosporine] indicated that β‐TPA‐responsive protein kinases were not involved. Accordingly, CLF and RA regulate biosynthesis and degradation of ethanolamine and choline phosphoglycerides in cultured skin fibroblasts by different mechanisms that do not involve classical protein kinase C (PKC) isoforms, even though turnover of phospholipids generating lipid activators of PKC occurs.
Sterol specificity of theSaccharomyces cerevisiae ERG6 gene product expressed inEscherichia coli
Authors: Venkatramesh Mylavarapu , Guo De‐an , Harman James G. , Nes W. David 
Published: November 2006

AbstractTheERG6 gene fromSaccharomyces cerevisiae has been functionally expressed inEscherichia coli, for the first time, yielding a protein that catalyzes the bisubstrate transfer reaction whereby the reactive methyl group from (S)‐adenosyl‐l‐methionine is transferred stereoselectively to C‐24 of the sterol side chain. The structural requirements of sterol in binding and catalysis were similar to the native protein fromS. cerevisiae. Inhibition of biomethylation was observed with fecosterol and ergosterol which suggests that ergosterol may function in wild‐type yeast as a feedback regulator of sterol biosynthesis.
Comparative hypocholesterolemic effects of six vegetable oils in cholesterol‐fed rat
Authors: Fukushima Michihiro , Akiba Shiori , Nakano Masuo 
Published: November 2006

AbstractThe hypocholesterolemic efficacies of various polyunsaturated fatty acids were compared in rats given cholesterol‐enriched diets.Oenothera biennis Linn oil (OBLO, linoleic +γ‐linolenic), sunflower oil (linoleic), palm oil (PLO, oleic+linoleic), soybean oil (linoleic+α‐linolenic), high‐oleic safflower oil (oleic+linoleic), or mixed oil (linoleic+α‐linolenic) was added to the diet at 200 g/kg (20% groups). OBLO was also added at 100 g/kg diet (10% group). The serum total and very low density lipoprotein+intermediate lipoprotein+low density lipoprotein cholesterol concentrations of the 10 and 20% OBLO groups were consistently lower than those in the other groups. The liver cholesterol concentration in the PLO group was lower in all groups. The liver cholesterol concentrations in the 10 and 20% OBLO groups were also lower than in the other groups. There were no significant differences in the fecal neutral sterol and bile acid extraction among groups.
A rapid method for separation of plasma low and high density lipoproteins for tocopherol and carotenoid analyses
Authors: Vogel Silke , Contois John H. , Couch Sarah C. , Lammi‐Keefe Carol J. 
Published: November 2006

AbstractUltracentrifugation (UC) is the method most often employed for separation and quantification of lipoproteins. Because this procedure requires expensive laboratory equipment, a large volume of fresh sample and an inordinate amount of time, it may not be ideal for routine clinical/experimental use. The aim of the current study was to evaluate a method which combines selective precipitation (HDL‐P) and immunoseparation (LDL‐I) for the rapid and reliable isolation of high density lipoproteins (HDL) and low density lipoproteins (LDL) specifically for vitamin E and carotenoid determination within these fractions. Cholesterol and triacylglycerol concentrations within the HDL and LDL were also determined to enable expression of vitamin E and carotenoid concentrations per gram of lipid. Isolation of lipoproteins by UC was used as the reference method (HDL‐UC/LDL‐UC). There were no significant differences between methods for α‐and γ‐tocopherol in LDL and HDL. Carotenoids measured in HDL and LDL were comparable between the methods. The exception was higher lutein/zeaxanthin concentration in HDL‐P and LDL‐I compared to HDL‐UC and LDL‐UC, respectively. Additionally, lycopene concentration was significantly lower in LDL‐I compared to LDL‐UC. In comparing vitamin E and carotenoid values in lipoproteins separated from fresh and frozen plasma by the direct method, there was no difference in α‐tocopherol or the majority of carotenoids measured. In conclusion, a combination of selective precipitation and immunoseparation of fresh or frozen plasma for subsequent α‐and γ‐tocopherol analyses provides an accurate and reliable alternative to lipoprotein separation by UC. Additionally, carotenoid concentrations in HDL separated by selective precipitation and analyses of α‐and β‐carotenes and β‐cryptoxanthin in LDL separated by immunoseparation are also reliable, while lycopene and lutein/zeaxanthin concentrations in LDL‐I are not readily comparable to LDL‐UC.
Neutral sterols of sawflies (symphyta): Their relationship to other hymenoptera
Authors: Schiff Nathan M. , Feldlaufer Mark F. 
Published: November 2006

AbstractTo investigate sterol utilization in sawflies, the neutral sterols of four species of sawflies were determined by gas‐liquid chromatography and mass spectrometry, and compared to the respective dietary plant material. Cholesterol was the predominant (55–76%) sterol in all species and stages of sawflies examined. Host plants, however, contained primarily sitosterol (50–88%), along with other 24‐alkylsterols and only 0.5–5.9% cholesterol, indicating that the sawflies examined are capable of dealkylating the C28 and C29 phytosterols in their diet to cholesterol. Comparative sterol metabolism in Hymenoptera is discussed.
Identification of a novel all‐cis‐5,9,12‐Heptadecatrienoic acid in the cellular slime moldPolysphondylium pallidum
Authors: Saito Tamao , Ochiai Hiroshi 
Published: November 2006

AbstractThe all‐cis‐5,9,12‐heptadecatrienoic acid was identified in the cellular slime moldPolysphondylium pallidum. The structural elucidation was accomplished by capillary gas chromatography, argentation thin‐layer chromatography, and gas chromatography/mass spectrometry. This fatty acid has not been reported previously.
A diet containing myristoleic plus palmitoleic acids elevates plasma cholesterol in young growing swine
Authors: Smith Dana R. , Knabe Darrell A. , Russell Cross H. , Smith Stephen B. 
Published: November 2006

AbstractThe objective of this study was to test the effect of a novel fatty acid mixture, enriched with myristoleic and palmitoleic acids, on plasma lipoprotein cholesterol concentrations. Weanling pigs were assigned to one of six groups and each group received a diet differing in fatty acid composition. Diets were fed for 35 days and contained 10 g added cornstarch/100 g (to provide baseline data) or 10 g added fatty acids/100 g. For those diets containing added fatty acids, extracted lipids contained 36% myristoleic plus palmitoleic acid combined (14∶1/16∶1 diet), 52% palmitic acid (16∶0 diet), 51% stearic acid (18∶0 diet), 47% oleic acid (18∶1 diet), or 38% linoleic acid (18∶2 diet). Witht the exception of the cornstarch diet, all diets contained approximately 30% myristic acid. There were no significant differences in weight gain across treatment groups (P=0.22). All diets caused a significant increase in triglycerides and in total, low density lipoprotein, high density lipoprotein, and very low density lipoprotein cholesterol. The increase in total plasma cholesterol from pretreatment values was greatest in pigs fed the 14∶1/16∶1 and 18∶1 diets. However, the increase in low density lipoprotein cholesterol from the pretreatment concentration was greatest in the 14∶1/16∶1‐fed pigs. Increases in very low density lipoprotein cholesterol above pretreatment concentrations were lowest in 16∶0‐fed pigs and greatest in 18∶1‐fed pigs. Dietary fatty acids elicited changes in plasma fatty acids which generally were reflective of the diets, although the 18∶0 diet did not alter plasma fatty acid concentrations and the 16∶0 diet increased plasma 16∶0 only at the end of the study. These results demonstrated that the combination of myristoleic plus palmitoleic acids increased plasma cholesterol in young pigs, suggesting that fatty acid chain length, rather than degree of unsaturation, is primarily responsible for the effects of fatty acids on circulating lipoprotein cholesterol concentrations.
Fatty acid carbon isotope ratios in humans on controlled diets
Authors: Rhee Sue K. , Reed Roberta G. , Brenna J. Thomas 
Published: November 2006

AbstractCarbon stable isotope ratios for six serum fatty acids (FA) are reported for human subjects on controlled fat diets to determine the range of natural isotope abundance and to demonstrate the leveling effect of a well‐controlled diet. Twenty‐nine subjects were randomly assigned to one of three controlled diets containing high, medium, or low fat. Diets were consumed for 8 wk. Serum samples were collected at baseline (0), 5, 6, 7, and 8 wk. FA were extracted and methylated. Isotope ratios were analyzed by high‐precision gas chromatography combustion‐isotope ratio mass spectrometry. At baseline, mean δ13C for 16:0b, 16:1a, 18:0a, 18:1c, 18:2n−6d, and 20:4n−6bc were −24.1, −21.7, −21.6, −25.6, −29.6, and −25.0%., respectively, with an average standard deviation of 1.9%.. Most δ13C decreased during the diet period and appeared to have stabilized by week 5 at −25.3, −21.9, −22.3, −26.5, −30.1, and −24.5%., respectively. Between‐subject variability decreased from 1.74 to 1.20%. on the controlled diets. Measurement variability was 0.53%.. The within‐subject variability during weeks 5–8 was 0.57%. (range of 0.32–0.84%.), showing a minimum biological fluctuation on controlled diets. There was no diet group effect on δ13C of serum FA. Except for 18:2, the δ13C of experimental diets was lower than that of serum FA, consistent with observations in animals. These data show that carbon isotope ratios stabilize in response to controlled diets within 5 wk, reflecting the isotope ratio of their dietary source, and establish isotope ratio fluctuations for endogenous compounds for future studies.
Sterol utilization and metabolism by Heliothis zea
Authors: Nes W. David , Lopez Monica , Zhou Wen , Guo De‐an , Dowd Patrick F. , Norton Robert A. 
Published: November 2006

AbstractHeliothis zea (corn earworm), an insect that fails to synthesize sterols de novo, was reared on an artificial diet treated with 18 different sterol supplements. Larvea did not develop on a sterol‐less medium. Δ5‐Sterols with a hydrogen atom, a methylene group, an E‐or Z‐ethylidene group, or an α‐ or β‐ethyl group (cholesterol, ostreasterol, isofucosterol, fucosterol, sitosterol, and clionasterol, respectively) at position C‐24, and Δ5‐sterols doubly substituted in the side chain at C‐24 with an α‐ethyl group and at C‐22 with a double bond (stigmasterol) supported normal larval growth to late‐sixth instar (prepupal: maturity). The major sterol isolated from each of these sterol treatments was cholesterol, suggesting that H. zea operates a typical 24‐dealkylation pathway. The sterol requirement of H. zea could not be met satisfactorily by derivatives of 3β‐cholestanol with a 9β, 19‐cyclopropyl group, gem dimethyl group at C‐4, a Δ5,7‐bond or Δ8‐bond, or by side‐chain modified sterols that possessed a Δ25(27)‐24β‐ethyl group, Δ23(24)‐24‐methyl group, or 24‐ethyl group, or Δ24(25)‐24‐methyl or 24‐ethyl group. The major sterol recovered from the larvae (albeit developmentally arrested larvae) treated with a nonutilizable sterol was the test compound. Sterol absorption was related to the degree of sterol utilization. The most effective sterols absorbed by the insect ranged from 27 to 66 μg per insect, whereas the least effective sterols absorbed by the insect ranged from 0.6 to 6 μg per insect. Competition experiments using different proportions of cholesterol and 24‐dihydrolanosterol (from 9:1 to 1:9 mixtures) indicated that abnormal development of H. zea may be induced on less than a 1 to 1 mixture of utilizable (cholesterol) to nonutilizable (24‐dihydrolanosterol) sterols. The results demonstrate new structural requirements for sterol utilization and metabolism by insects, particularly with respect to the position of double bonds in the side chain and functionalization in the nucleus. The novel sterol specificities observed in this study appear to be associated with the dual role of sterols as membrane inserts (nonmetabolic) and as precursors to the ecdysteroids (metabolic).
Synthesis and molecular modeling: Related approaches to progress in brassinosteroid research
Authors: Brosa Carme , Zamora Ismael , Terricabras Emma , Soca Lídia , Peracaula Rosa , Rodríguez‐Santamarta Carlos 
Published: November 2006

AbstractIn the field of brassinosteroids, which are potent plant growth regulators, we have developed a quantitative structure‐activity relationship study to develop knowledge from a structural point of view and to find out new requirement definitions. This will help identify other suitable active brassinosteroid derivatives with a good activity/synthetic cost ratio for further application in agriculture. The methodology used to achieve this goal represents a multidisciplinary study involving synthesis, molecular modeling calculations, and bioactivity evaluation. The influence of different molecular properties in the bioactivity of a set of synthetic compounds (i.e., molecular electrostatic potential and the ability to form H bonds) is discussed. The molecular electrostatic potential is expressed in terms of the electrostatic Carbó similarity index (Cl) between brassinolide (1) and other brassinosteroids. We have found that the electrostatic charges of the functional groups play an important role in the description of the activity, as evidenced by its good correlation with the Cl in most cases. Deviation from this rule could be explained by the H bonding abilities of some of these compounds, which we believe may play an essential role in binding to the natural receptors.
Women's Barrier Contraceptive Methods: Poised for Change
Authors: Narrigan Deborah 
Published: November 2006

ABSTRACTOver the past 20 years, the number of women in the United States choosing a cervical barrier contraceptive method has dramatically declined. By 2002, fewer than 3% of women reported using any woman‐initiated barrier method, including the diaphragm, female condom, or cervical cap. At the same time, however, research in infectious diseases indicates that cervical barriers may effectively prevent the transmission of several sexually transmitted infection. This possibility has fueled the recent development of two novel devices. This article examines the seven devices currently available in the United States, comparing their characteristics, efficacy, benefits, and drawbacks. Compared to the diaphragm, the new devices do not offer improved odds of pregnancy prevention, and evidence for their efficacy is sparse. Reasons for the limited acceptance of these methods as contraceptives on one hand—and for interest in their potential for limiting sexually transmitted infections on the other—will also be reviewed. Despite the limited acceptance of cervical barrier methods, midwives and other clinicians should promote their availability as an alternative to other reversible contraceptives.
Providing Quality Care to the Sexual Assault Survivor: Education and Training for Medical Professionals
Authors: Ferguson Cynthia 
Published: November 2006

ABSTRACTHealth care providers who perform sexual assault examinations can assist patients who report experiencing a sexual assault by increasing their knowledge and skills in sexual assault care, and serving as Sexual Assault Response Team (SART) coordinators, or as SART team members, in their communities. With little additional material, this training could be provided as a component of basic midwifery and/or advanced practice nursing education programs. This article reviews the essential steps and required training for conducting sexual assault examinations.
Large Vestibular Aqueduct Syndrome: A Human Temporal Bone Study
Authors: Hirai Shigeo , Cureoglu Sebahattin , Schachern Patricia A. , Hayashi Hideo , Paparella Michael M. , Harada Tamotsu 
Published: November 2006

AbstractObjectives/Hypothesis: Large vestibular aqueduct syndrome (LVAS) is one of the common causes of hearing loss (HL). All prior studies have reported some anomalies associated with LVAS by imaging techniques. This study was undertaken to determine prevalence of LVAS in our temporal bone (TB) collection and its relationship to other systemic or otologic anomalies.Study Design: Retrospective, TB histopathologic study.Methods: Anteroposterior diameters of internal (IA) and external (EA) apertures were measured in 40 normal TBs (40 cases). TBs were considered as large vestibular aqueduct (LVA) if width of apertures was 95% greater than “normals.” Systemic and otologic anomalies and histopathology of ears with LVAS were noted.Result: Of 1,608 non‐“normal” TBs, 63 had LVA. There was negative correlation between IA and EA in 48 TBs with only enlarged IA. Fifteen TBs with enlarged EA always had enlarged IA and were therefore considered as LVAS. The most common pathologic condition was congenital heart anomaly. The most common syndrome or dysplasia was Mondini's. The most common anomalies of external and middle ears were dehiscent facial nerves, low set auricles, and ossicular deformities. Inner ear anomalies included modiolar deficiencies, hair cell loss, interscalar septum defects, and strial atrophy. There was no record of family history of HL, head injury, or craniofacial, branchial, or thyroidal abnormalities.Conclusion: Because HL associated with LVAS may be attributed to other ear anomalies, it is important to investigate other inner ear problems and system diagnoses that may indicate a syndrome in patients with radiologically diagnosed LVAS.