bluuebunny/crossref_metadata_2025 huggingface dataset:
MCMC‐based linkage analysis for complex traits on general pedigrees: multipoint analysis with a two‐locus model and a polygenic component
Authors: Sung Yun Ju , Thompson Elizabeth A. , Wijsman Ellen M.
Published: November 2006

We describe a new program lm_twoqtl, part of the MORGAN package, for parametric linkage analysis with a quantitative trait locus (QTL) model having one or two QTLs and a polygenic component, which models additional familial correlation from other unlinked QTLs. The program has no restriction on number of markers or complexity of pedigrees, facilitating use of more complex models with general pedigrees. This is the first available program that can handle a model with both two QTLs and a polygenic component. Competing programs use only simpler models: one QTL, one QTL plus a polygenic component, or variance components (VC). Use of simple models when they are incorrect, as for complex traits that are influenced by multiple genes, can bias estimates of QTL location or reduce power to detect linkage. We compute the likelihood with Markov Chain Monte Carlo (MCMC) realization of segregation indicators at the hypothesized QTL locations conditional on marker data, summation over phased multilocus genotypes of founders, and peeling of the polygenic component. Simulated examples, with various sized pedigrees, show that two‐QTL analysis correctly identifies the location of both QTLs, even when they are closely linked, whereas other analyses, including the VC approach, fail to identify the location of QTLs with modest contribution. Our examples illustrate the advantage of parametric linkage analysis with two QTLs, which provides higher power for linkage detection and better localization than use of simpler models. Genet. Epidemiol. © 2006 Wiley‐Liss, Inc.
Cordectomy by CO2 laser or radiotherapy for small T1a glottic carcinomas: Costs, local control, survival, quality of life, and voice quality
Authors: Goor Kim M. , Peeters A. Jeanne G. E. , Mahieu Hans F. , Langendijk Johannes A. , Leemans C. René , Verdonck‐de Leeuw Irma M. , van Agthoven Michel
Published: November 2006

Background.

The clinical results of radiotherapy and endoscopic cordectomy for T1a glottic carcinoma are reported to be similar, but costs of both treatments may differ. Therefore, we retrospectively evaluated the costs, voice quality, quality of life, and clinical results of both treatments.

Methods.

Costs and effects from the first visit up to 2 years of follow‐up were calculated, based on chart data of 35 and 54 patients who were treated with curative intent for T1a glottic carcinoma from 1995 to 1999 with radiotherapy and endoscopic cordectomy, respectively. Voice quality and quality of life were evaluated by means of patient questionnaires.

Results.

Total costs (in Euros) of radiotherapy and CO2‐laser cordectomy were €8322 and €4434, respectively, including the costs of treating possible recurrences. The effects of both treatments were equal, including voice quality and quality of life.

Conclusions.

We conclude that endoscopic cordectomy is an efficient alternative for radiotherapy for these patients. © 2006 Wiley Periodicals, Inc. Head Neck, 2007
The use of a linkage analysis as evidence in the conviction of the Newcastle serial murderer, South Africa
Authors: Labuschagne Gérard N.
Published: November 2006

The linking of a series of crimes to one individual has always been problematic, especially in the absence of eyewitness or forensic evidence. During the investigation, another means whereby this can be done is through linkage analysis. Yet a linkage analysis can also play a role during the trial of a serial offender. This paper examines the use of a linkage analysis report as evidence during the trial of the Newcastle serial murderer in South Africa. The linkage analysis examined the circumstances of the crime, modus operandi, and signature behaviour of the offender, to come to the conclusion that all the offences were committed by one individual, despite the lack of eyewitness or forensic evidence linking the suspect to two of the four incidents. This evidence was admitted by the court and the presiding officer concurred that the accused was guilty of committing the crimes during the third and fourth incidents. Copyright © 2006 John Wiley & Sons, Ltd.
Infrared and Raman spectroscopic studies of L‐valinium picrate
Authors: Senthilkumar S. , Briget Mary M. , Ramakrishnan V.
Published: November 2006

The vibrational assignments of the observed wavenumbers have been made by analyzing the infrared and Raman spectra of L‐valinium picrate in the crystalline state at room temperature. L‐Valinium acts as the cation of the crystal and the carbonyl CO group exists in the protonated form in it. Asymmetric deformation and symmetric deformation modes of the isopropyl group have been identified, indicating that the two CH3 groups are in different environments. The stretching and bending modes of the various functional groups have been shifted owing to the extensive intermolecular hydrogen bonding in the crystal. The symmetry of the picrate anion has not been modified in the crystal by the hydrogen bonding with the cation. Fermi resonance is also observed. Copyright © 2006 John Wiley & Sons, Ltd.
Comparison between prospective and retrospective triggering for mouse cardiac MRI
Authors: Heijman Edwin , de Graaf Wolter , Niessen Petra , Nauerth Arno , van Eys Guillaume , de Graaf Larry , Nicolay Klaas , Strijkers Gustav J.
Published: November 2006

High‐resolution magnetic resonance imaging (MRI) has evolved into one of the major non‐invasive tools to study the healthy and diseased mouse heart. This study presents a Cartesian CINE MRI protocol based on a fast low‐angle shot sequence with a navigator echo to generate cardiac triggering and respiratory gating signals retrospectively, making the use of ECG leads and respiratory motion sensors obsolete. MRI of the in vivo mouse heart using this sequence resulted in CINE images with no detectable cardiac and respiratory motion artefacts. The retrospective method allows for steady‐state imaging of the mouse heart, which is essential for quantitative contrast‐enhanced MRI studies. A comparison was made between prospective and retrospective methods in terms of the signal‐to‐noise ratio and the contrast‐to‐noise ratio between blood and myocardial wall, as well as global cardiac functional indices: end‐diastolic volume, end‐systolic volume, stroke volume and ejection fraction. The retrospective method resulted in almost constant left‐ventricle wall signal intensity throughout the cardiac cycle, at the expense of a decrease in the signal‐to‐noise ratio and the contrast‐to‐noise ratio between blood and myocardial wall as compared with the prospective method. Prospective and retrospective sequences yielded comparable global cardiac functional indices. The largest mean relative difference found was 8% for the end‐systolic volume. Copyright © 2006 John Wiley & Sons, Ltd.
Strain effects during coherent spin transport via moving quantum dots
Authors: Stotz J. A. H. , Santos P. V. , Hey R. , Ploog K. H.
Published: November 2006

The geometry of the sample is shown to dictate the importance of strain on the spin‐orbit splitting of the conduction band for electrons transported via dynamic quantum dots (DQDs) generated by surface acoustic waves (SAWs). Photoluminescence measurements monitoring the Larmor precession of electron spins in the absence of an applied magnetic field are used to characterize the spin‐orbit splitting of the conduction band. We show that, in thick quantum wells (QWs), the Dresselhaus spin‐orbit contribution to the precession frequency reduces and may become comparable to the one associated with the strain field induced by the SAW. We attribute deviations in the measured precession frequency to strain effects, which become more pronounced for QWs located closer to the surface because of the larger SAW strain field. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Laplace DLTS studies on deep levels coexisted with InAs quantum dots
Authors: Lin S. W. , Peaker A. R. , Song A. M.
Published: November 2006

Self‐assembled InAs/GaAs quantum dot structures have been investigated in both conventional and Laplace‐transform deep‐level transient spectroscopy (DLTS) experiments. Laplace DLTS technique provides orders of magnitude better energy resolution than conventional DLTS and hence enables us to study the electronic fine structure of the deep level states that are revealed using the conventional DLTS method. Two well‐separated peaks corresponding to excitation energies of 468 meV and 485 meV are determined in the quantum dot sample, which have energy broadenings of 13.7 meV and 22.9 meV, respectively. A fine structure is also observed in the reference sample, but the ratio between the two peaks differs and the energy broadening is too narrow to be resolved even by the Laplace DLTS. The strain relaxation due to the QD formation is proposed to explain our observations. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Emission at 1.55 µm from InAs/GaAs quantum dots grown by metal organic chemical vapor deposition via antimony incorporation
Authors: Guimard Denis , Tsukamoto Shiro , Nishioka Masao , Arakawa Yasuhiko
Published: November 2006

By introducing antimony during the growth of InAs/GaAs quantum dots (QDs) by metalorganic chemical vapor deposition, we have achieved ground‐state emission at 1.55 µm (and beyond) from InAs/GaAs QDs capped by an In0.24Ga0.76As strain‐reducing layer (SRL) at room temperature (RT). We show that antimony irradiation results in the formation of QD sub‐ensembles. Photoluminescence intensity is strongly enhanced (×100) at RT compared to Sb‐free QDs capped by higher In‐content SRL in which ground‐state emission saturates at wavelengths shorter than 1.51 µm. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Phonon‐induced electron relaxation in correlated quantum dots
Authors: Climente Juan I. , Bertoni Andrea , Rontani Massimo , Goldoni Guido , Molinari Elisa
Published: November 2006

We study the electron momentum relaxation in single and vertically coupled quantum dots due to coupling with acoustic phonons. We consider both the single‐electron and the few‐electron regimes, using a Full Configuration Interaction approach to account for the electron‐electron repulsion. Our findings suggest that electronic correlations tend to reduce intradot and interdot transition rates. We also show that external magnetic fields acting on properly designed quantum dots may strongly suppress electron‐phonon coupling. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Power dependent photoluminescence of lateral quantum dot molecules: Indication of extended electron states
Authors: v. Lippen T. , Nötzel R. , Eijkemans T. J. , Bogaart E. W. , Wolter J. H.
Published: November 2006

Excitation power density dependent photoluminescence (PL) measurements of an ensemble of ordered lateral quantum dot (QD) molecules containing on average 4 and 8 QDs are carried out. Asymmetric broadening of the PL spectra is observed with increasing excitation power density which is stronger for 8 QDs per molecule than for 4 QDs. In addition, a shift of the PL peak to higher energies occurs. In p‐type modulation‐doped QD molecules the asymmetric broadening and high‐energy shift are enhanced. N‐type modulation‐doped QD molecules exhibit a square‐shaped PL spectrum, resembling that of modulation‐doped quantum wells. These findings are consistently explained by state filling in the presence of extended electron states due to lateral electronic coupling of the QDs within the molecules forming a quasi two‐dimensional density of states. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical characterisation of single InAs quantum dots on GaAs substrate emitting at 1.3 μm
Authors: Chauvin N. , Baira M. , Bru‐Chevallier C. , Ilahi B. , Sfaxi L. , Maaref H.
Published: November 2006

Single InAs/GaAs quantum dots are studied using micro‐photoluminescence spectroscopy. Single dot spectroscopy shows an antibinding biexciton. Some of these quantum dots are laterally coupled due to an anisotropic dot repartition. At low excitation power density, four excitons emissions are observed and are interpreted as the four possible exciton recombinations of two coupled quantum dots. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of ribosomal proteins as biomarkers for matrix‐assisted laser desorption/ionization mass spectral identification of Lactobacillus plantarum
Authors: Sun Liwei , Teramoto Kanae , Sato Hiroaki , Torimura Masaki , Tao Hiroaki , Shintani Tomoyoshi
Published: November 2006

For rapid identification of bacteria by matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS), a bioinformatics approach using ribosomal subunit proteins as biomarkers has been proposed. This method compares the observed masses for biomarkers with calculated masses as predicted from the amino acid sequences registered on protein databases. To evaluate this approach, the expressed ribosomal proteins of a genome‐sequenced bacterium, Lactobacillus plantarum NCIMB 8826, were characterized as a model sample. The protein expression of 42 ribosomal subunit proteins, together with 10 ribosome‐associated proteins in the isolated ribosome fraction, was confirmed through two‐dimensional gel electrophoresis combined with peptide mass fingerprinting. The observed masses of the proteins in the isolated ribosome fraction were then determined by MALDI‐MS. We preliminarily selected 44 biomarkers whose observed masses were matched with the calculated masses predicted from the amino acid sequence registered in the protein databases by considering N‐terminal methionine loss only. Of these, the finally selected reliable biomarkers were 34 proteins including 31 ribosomal subunit proteins and 3 ribosome‐associated proteins that could be observed in the MALDI mass spectra of the cell lysate sample. These biomarkers were usable in MALDI‐MS characterization of two industrial L. plantarum cultures. Copyright © 2006 John Wiley & Sons, Ltd.
Determining barriers to sustainability within the Costa Rican coffee industry
Authors: Adams M. A. , Ghaly A. E.
Published: November 2006

The Costa Rican coffee industry has been the subject of many sustainability plans, all of which have had a particular bias towards one aspect of sustainability or another. Following the sustainability evaluation framework discussed in previous work a significant gap was recognized between the requirements of a sustainable industry, which address all facets of sustainability (including all stakeholders – both producers and processors), and the present system. This was particularly so within aspects of institutional considerations and the lack of continuity when integrating processing considerations into sustainability considerations. The concerns, deficiencies and perceptions of the various stakeholders within the industry were documented in order to ensure a proper match between sustainability barriers and any steps that would be taken to address them. The inclusion of stakeholders' thoughts and perceptions was determined to be important in the establishment of any policy aimed at improving the overall sustainability of the coffee industry. Using the sustainability framework as the foundation for discussion, specific barriers to the application of sustainability were highlighted and discussed. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.
The purification and specificity of a lipase fromVernonia anthelmintica seed
Authors: Olney C. E. , Jensen R. G. , Sampugna J. , Quinn J. G.
Published: November 2006

Acetone powders prepared fromVernonia anthelmintica seed catalyzed the release of 6.4 to 9.6 μ‐moles of free fatty acids per milligram of protein when blended with olive oil and phosphate buffer and shaken for 20 min at 43 C. A 20 fold purification was achieved by differential centrifugation of an ammonium hydroxide extract of the acetone powder. Results from Sephadex G‐200 chromatography and polyacrylamide gel electrophoresis suggested that the lipase activity was associated with a molecule of molecular weight greater than 200,000. Free fatty acids, 1,2‐ and 1,3‐diglycerides, monoglycerides and glycerol were found in the digestion products. With most substrates the 1,2‐to 1,3‐diglyceride ratio was approximately 2∶1 and monoglycerides tended to accumulate. Analysis of the digestion products from synthetic triglycerides of known structure indicated that both primary and secondary ester positions of the triglyceride molecule were hydrolyzed and that considerable isomerization of 1,2‐diglyceride to 1,3‐diglyceride occurred. The monoglyceride was consistently lower than the 1,2‐diglyceride and in the majority of cases also lower than the 1,3‐diglyceride in the fatty acid originally present in the 2 position of the triglyceride. No fatty acid preference was observed.
The effect of antioxidant deficiency on tissue lipid composition in the rat. III. Testes
Authors: Witting L. A. , Likhite V. N. , Horwitt M. K.
Published: November 2006

Production of testicular degeneration in the antioxidant‐deficient rat resembles encephalomalacia in the chick in its dependence on essential (ω6) fatty acids and is distinct from the generalized response to all polyunsaturated fatty acids seen in nutritional muscular dystrophy in the rat. The nonessential (ω3) polyunsaturated fatty acids, however, lower the essential fatty acid content of the testicular lipids only slightly, are not themselves incorporated into this tissue to any appreciable degree and thus do not show the inhibitory effect on production of the antioxidant‐deficiency sign noted in the studies on encephalomalacia. A direct relationship between the essential fatty acid content of the testes and the rate of testicular degeneration was found, but no effects of biologically available selenium and sulfur amino acids were evident. As the liver and muscle, onset of antioxidant‐deficiency is characterized by a decrease in the most highly unsaturated fatty acid in the tissue (22∶5–ω6 in this case) and a net increase in arachidonate.
The effect of antioxidant deficiency on tissue lipid composition in the rat. IV. Peroxidation and interconversion of polyunsaturated fatty acids in muscle phospholipids
Authors: Witting L. A.
Published: November 2006

It has been suggested that the net changes which take place in the composition of the muscle phospholipid fatty acids of the antioxidant‐deficient rat represent the balance of two opposing processes. To compensate for (A) the preferential peroxidative destruction of the most highly polyunsaturated fatty acids in the tissue there occurs (B) an increase in the conversion of available precursors to the higher polyunsaturated fatty acids. Analysis of the data in terms of peroxidation kinetics indicated that the onset of creatinuria in one group after 3 weeks and in a second group after 7 weeks on an antioxidant‐deficient diet occurred in both cases concomitant with the peroxidative “disappearance” of approximately 125 μg of phospholipid polyunsaturated fatty acid per gram wet weight of tissue or 2% of the total muscle phospholipid fatty acids.
Mechanism of suckling‐rat hypercholesteremia. II. Cholesterol biosynthesis and cholic acid turnover studies
Authors: Harris R. A. , Rivera E. R. , Villemez C. L. , Quackenbush F. W.
Published: November 2006

Cholesterol biosynthesis from acetate‐2‐14C by the livers of suckling rats, which is known to be relatively slow, was increased 2–3‐fold within 24 hours after severing the bile duct. Cholesterol synthesis by sham‐operated litter mates showed no change under similar treatment. Mevalonate biosynthesis from acetate‐2‐14C in vitro by recombined liver microsomal supernatant (105,000×g) fractions from suckling rats also was only 10% of that of comparable recombined fractions from normal controls (young adult rats which were consuming colony diet). Activity was not improved by combining either the microsomal or supernatant fraction from suckling rat livers with the complementary fraction from normal adult livers. On the other hand, activity was restored to 100% when microsomes from livers of duct‐served suckling rats were combined with the supernatant fraction from normal controls. Likewise, recombined liver fractions prepared from adult rats fed synthetic diets exhibited low activity for mevalonate biosynthesis. Activity was restored by bile duct cannulation, but inhibited when cholic acid was infused into the cannulated animal. Therefore, surgical procedures which interrupt the enterohepatic recirculation of bile components lead to a restoration of cholesterol biosynthesis and, at least in the adult animal where cannulation studies are practicable, this effect can be reversed readily by bile acid infusion.

A slow rate of fecal excretion of14C‐cholic acid was observed in suckling rats and rats fed synthetic diets, apparently reflecting an efficient enterohepatic recirculation of bile salts. The data suggest that under these dietary conditions bile salt retention either directly or indirectly influences hepatic synthesis of cholesterol.
Metabolism of unsaturated fatty acids in the intestine
Authors: Bottino Nestor R.
Published: November 2006

Rats fed a fat‐free diet from weaning were contined on that diet alone or supplemented with methyl linoleate, methyl linoleate plus a mixture of antibiotics, or methyl arachidonate.

Dietary linoleate and arachidonate reduced the concentration of octadecenoic acid and increased that of stearic acid in the mucosa and luminal lipids. This effect was prevented in the mucosa but not in the intestinal contents by antibiotic supplementation of the linoleate diet.

Evidence for the conversion of linoleic into eicosatetraenoic acid was found in both mucosa and luminal lipids. The conversion was impaired by the addition of antibiotics to the diet.

Linoleate feeding combined with antibiotic addition provided evidence for the intestinal hydrogenation of dietary linoleic into either octadecenoic or stearic acids by separate routes, the latter being impaired by antibiotic ingestion.

The ingestion of methyl linoleate or arachidonate modified only slightly the fecal fatty acid pattern of rats previously on a fat‐free diet.
Dietary fat effect on incorporation and release of lipids and cholesterol by rat intestinal slices
Authors: Pawar Sitaram S. , Tidwell Herbert C.
Published: November 2006

The effect of saturated and unsaturated fats on in vitro formation and release of lipids and cholesterol from14C acetate by rat intestinal tissue was investigated. The rats were fed a basal diet enriched with either 25% corn oil or lard and then sacrificed after a 10‐ or 25‐day feeding period. It was observed that a similar14C lipid content but a greater14C cholesterol content was found in the intestinal tissue of rats fed corn oil than in rats fed lard for 10 days. After a longer period of feeding of 25 days, the intestinal tissue14C cholesterol level was decreased in the corn oil fed rats without any significant effect on other lipids. These data suggest that corn oil in some way influences cholesterol biosynthesis depending upon its degree of unsaturation and the period of time for which it is fed. The decrease at the later time might involve some mechanism which aids in getting rid of accumulated tissue cholesterol. Less14C lipid and14C cholesterol were released by the intestinal tissue of rats fed the unsaturated fat as compared with those fed the saturated fat, suggesting a possible role in vivo in reducing blood lipids and blood cholesterol levels.
In vitro incorporation of acetate‐1‐14C into the phospholipids of rabbit and human endometria
Authors: Morin Robert J. , Carrion Maria
Published: November 2006

Endometria from nonpregnant and 6‐day pregnant rabbits and from humans in the proliferative and secretory phases were incubated with 1‐14C‐acetate.14CO2 was collected, and subsequently the amounts, specific radioactivities, and in some cases the fatty acid compositions of the isolated phospholipids were determined. Phosphatidyl choline was the phospholipid present in highest amount in endometria from both nonpregnant and pregnant rabbits, and in human endometria; this phospholipid also showed the highest degree of incorporation of14C‐acetate. Pregnancy in the rabbit seemed to decrease the incorporation of14C‐acetate into most of the endometrial phospholipid classes. In humans, the incorporation of acetate into phosphatidyl choline and phosphatidyl ethanolamine was lower in the secretory than the proliferative endometria.

Of the fatty acids, linoleic acid in phosphatidyl choline and phosphatidyl ethanolamine of the rabbit endometria showed a significant relative increase during pregnancy and palmitoleic acid showed a decrease.
The in vivo incorporation of labeled linoleic acid, α‐linolenic acid and arachidonic acid into rat liver lipids
Authors: De Tomas Maria Elena , Mercuri Osvaldo
Published: November 2006

The incorporation of 1‐14C‐linoleic acid, 1‐14C‐α‐linolenic acid and 1‐14C‐arachidonic acid into rat liver lipids was measured and the per cent distribution of radioactivity into the different lipid fractions determined. Normal rats were injected into the portal vein with the labeled solutions during a one minute period. Livers were quickly frozen, pulverized, and the lipids extracted and fractioned by thin layer chromatography. No significant differences were observed in the amounts of labeled fatty acids incorporated per gram of rat liver. While 1‐14C‐linoleic acid and 1‐14C‐α‐linolenic acid were found in appreciable amounts in the 1,2 diacylglycerol fraction, about one fifth as much 1‐14C‐arachidonic acid was esterified in this fraction. 1‐14C‐arachidonic acid was the leading acid esterified in the phospholipid fractions.
Response of rat adrenal cholesteryl esters to cold stress
Authors: Walker Brian L. , Carney James A.
Published: November 2006

Male rats were maintained on diets containing corn oil or hydrogenated coconut oil. The compositions of the adrenal cholesteryl esters were determined in control animals and in those subjected to cold stress (4 C for 30 min). Total sterol ester content was lower in the stressed rats. In those receiving corn oil there were selective decreases in 16∶1, 18∶2 and 20∶4(n−6) esters but not in 22∶4(n−6). In the coconut oil fed, essential fatty acid (EFA) deficient animals, the decreases in 20∶4(n−6) and 22∶4(n−6) were quite selective, but the concentrations of the cholesteryl esters of 20∶3(n−9) and 22∶3(n−9) were also selectively reduced in the stressed animals. Olive oil and corn oilethyl erucate were employed as dietary fats in a second experiment. Plasma corticosterone was lower in animal fed ethyl erucate and subjected to cold stress. Cholesteryl erucate was the major adrenal ester in animals receiving dietary erucate but it was not well utilized in animals subjected to stress. The cholesteryl esters of linoleate and arachidonate were preferentially utilized in both of these dietary groups. Cholesteryl arachidonate was selectively utilized in all four dietary groups studied and may constitute the preferred substrate for rat adrenal cholesteryl ester hydrolase.
A comparison of triglyceride, monoglyceride, and phospholipid substrates for post‐heparin lipolytic activities from normal and hypertriglyceridemic subjects
Authors: Vogel William C. , Brunzell John D. , Bierman Edwin L.
Published: November 2006

Evidence for heterogeneity of postheparin lipolytic activities in plasma was explored. After low or high doses of heparin, activities were measured in assays with phospholipid or monoglyceride substrate and with triglyceride substrate in assays using either calcium or albumin as the fatty acid acceptor. An excellent correlation between all assays was obtained in normals after both low and high doses of heparin over a wide range of individual response. In selected subjects with hypertriglyceridemia known to be deficient in response to heparin, all responses measured with phospholipid or triglyceride were below the lower limit of normal response. Some responses with monoglyceride substrate were within the normal range, pathophysiological evidence of a separate monoglyceridase. There was no evidence in either group of separate triglyceride lipase and phospholipase activities. The closest correlation between assays in normals was between triglyceride substrate with calcium as the fatty acid acceptor and the assay with monoglyceride. No differential effect upon lipolytic activities was found (1) after preincubation of the plasma, (2) with inhibitors in the assay, or (3) with preincubation of plasma and inhibitors prior to the assay.
Isolation and identification of cholesterol α‐oxide and other minor sterols in human serum
Authors: Gray M. F. , Lawrie T. D. V. , Brooks C. J. W.
Published: November 2006

The isolation and identification of cholesterol α‐oxide, coprostanol, β‐sitosterol, cholest‐4‐en‐3‐one and cholesta‐4, 6‐dien‐3‐one from human serum are reported. Compounds were isolated by thin layer chromatography and were identified by gas liquid chromatography and gas chromatography‐mass spectrometry (GC‐MS). Data for standard sterols are also reported. The possible origins of these minor components and the significance of their presence are discussed.
Metabolism of phospholipid in mammary gland: I. The supply of phospholipid for milk synthesis in the rat and goat
Authors: Easter D. J. , Patton S. , McCarthy R. D.
Published: November 2006

Data presented in this study demonstrate that under normal physiological conditions milk phospholipids in the rat and the goat originate predominantly, if not totally, by de novo synthesis within the mammary gland. Evidence to support this has been obtained for the goat by measurement of P32‐phosphate incorporation into milk phospholipids, and in the rat by measurement of P32‐phosphate incorporation and by feeding radioactive phospholipid to measure the incorporation of serum phospholipids into milk. The latter experiment showed that the fatty acid portion of the dietary phospholipid can readily be utilized by the mammary gland for triglyceride synthesis, but that the contribution of the serum phospholipid “backbone” to milk phospholipid is minimal.
On the origin of oil droplets in maturing castor bean seeds,Ricinus communis
Authors: Harwood J. L. , Sodja Ann , Stumpf P. K. , Spurr A. R.
Published: November 2006

Fat droplets isolated from maturing castor bean seeds contain high concentrations of fatty acid synthetase and triglyceride synthesizing enzymes. These activities are not due to contamination by other organelles and account for at least 80% of the total lipid synthesis. Electron microscopy of the isolated oil droplets and the seed tissue in vivo revealed particulate containing vacuole‐like inclusions which, it is suggested, are the site of lipid synthesis and which form the original locus of the droplet.
Early steps on the in vivo incorporation of 1‐14C‐linoleic acid into liver lipids from normal and essential fatty acid deficient rats
Authors: Mercuri Osvaldo , De Tomas Maria Elena
Published: November 2006

Essential fatty acid (EFA) deficient rats were injected intraportally with a solution of 1‐14C‐linoleic acid during a 1 min period. Livers were quickly frozen, pulverized, and the lipids extracted and fractioned by thin layer chromatography. The incorporation of 1‐14C‐linoleic acid into liver lipids was measured. The results were compared with those previously obtained from normal rats. No significant differences were observed in the total radioactivity recovered from lipid extracts. While the distribution of radioactivity into the 1–2 diacylglycerol fraction remained unchanged in both groups of rats, in the EFA deficient rats the 1‐14C‐linoleic acid incorporation was actually directed to the phospholipid fractions instead of to the triacylglycerol fractions as was observed in the normal rats.
Lipid composition of human bronchial mucus
Authors: Lewis R. W.
Published: November 2006

Mucus from an asthmatic patient contained lipids which have not been analyzed before. The composition was similar to two other types of mucus lipids. The triglyceride fraction was highly saturated and contained large amounts of short chain fatty acids.
Reactions of biological antioxidants: II. Fe(III)‐catalyzed reactions of methyl linoleate hydroperoxides with derivatives of coenzymes Q and vitamin E
Authors: Gruger E. H. , Tappel A. L.
Published: November 2006

Lipid free‐radical oxidations of ubiquinol‐6, ubichromenol‐6, ubichromenol‐10, and α‐tocopherol hydroquinone were kinetically examined in the presence of Fe(III)‐catalyzed dissociations of preformed methyl linoleate hydroperoxides. The rates of oxidation of the chromenols increased more than those of the hydroquinones as reaction acidity was increased. Differences in thermal effects upon rates were influenced by the levels of water in the reactions. The hydroquinones exhibited faster rates relative to α‐tocopherol than the ubichromenols, while the rates for the latter varied markedly depending on the nature of the solvent.
Determination of specific activity of isotopic materials by thin layer chromatography
Authors: Wortmann Wil , Kasparow Maria , Touchstone Joseph C.
Published: November 2006

A modified method for determination of specific activity by thin layer chromatography (TLC) is described. Based on in situ spectrodensitometry after separation by TLC, the method is rapid and requires amounts of reference material in the microgram range.
Phospholipid reactivation of plasmalogen metabolism
Authors: Ellingson John S. , Lands William E. M.
Published: November 2006

This report is concerned mainly with the properties of an enzyme from rat liver microsomes which hydrolyzes the alkenyl ether bond of 1‐(1′‐alk‐1′‐enyl)‐glycero‐3‐phosphoryl‐choline (alkenyl‐GPC hydrolase).

Destruction of the normal environment of the microsomes by treatment with phospholipases A or C caused inactivation of the alkenyl‐GPC hydrolase, which was then partially reactivated by the addition of exogenous phospholipids. Both sphingomyelin and diacyl‐GPC were efficient in restoring activity; diacyl‐GPE was less effective; and monoacyl‐GPC and monoacyl‐GPE were ineffective. The presence of two long hydrocarbon chains in the lipid activator is apparently required for reactivation, suggesting that interaction of hydrophobic areas of the enzyme with the phospholipid is necessary for maximal activity. High concentrations of sucrose mimicked the effect of phospholipids, and because the sucrose and diacyl‐GPC did not show an additive effect, they may reactivate the enzyme in a similar manner.

Disrupting the enzyme's environment by freezing and thawing the preparation also resulted in a loss of enzymatic activity, which was restored by added exogenous phospholipids.

The alkenyl‐GPC hydrolase was inhibited by imidazole and some of its derivatives. Histidine and N‐acetyl histidine did not inhibit the enzyme, presumably due to the presence of a negative charge on the carboxyl group rather than the steric bulk of that group, since histidine methyl ester did inhibit the enzyme. Kinetic evidence showed imidazole to be a competitive inhibitor. The enzymatic activity of imidazole‐treated microsomes also increased following addition of exogenous phospholipids. Imidazole inhibition differed from the phospholipase A‐inactivation in that it was partially reversed by KCl, but not by sucrose. Imidazole did not inhibit other microsomal enzymes tested, indicating that it is not a general inhibitor of membrane‐associated enzymes.
Quantitative determination of alk‐1‐enyl‐ and alkyl‐glyceryl ethers in neutral lipids and phospholipids
Authors: Wood Randall , Snyder Fred
Published: November 2006

A quantitative method for the simultaneous determination of alk‐l‐enyl‐ and alkyl‐glyceryl ethers is described. Complete hydrogenolysis of carboxylate and phosphate esters of neutral lipids and phospholipids was achieved with lithium aluminum hydride. The hydrogenolysis products of the glyceryl ether containing lipids, alk‐l‐enyl‐ and alkyl‐glyceryl ethers and alcohols, were identified by thin‐layer chromatography (TLC), gas‐liquid chromatography (GLC), and infrared spectroscopy. The alk‐l‐enyl‐ and alkyl‐glyceryl ethers were quantitated by TLC photodensitometry. The specificity of this method can also be extended when used in conjunction with GLC, ion‐complexing TLC, zonal scanning, and autoradiography to study composition, isomeric form, and the biosynthesis of glyceryl ethers in neutral and phospholipids.

The percentage of alk‐l‐enyl‐ and alkyl‐glyceryl ethers in bothtthe neutral lipids and phospholipids of various rat tissues was determined by the described method. Glyceryl ether glycerides represent 0.3–1.2% of the total neutral lipids whereas the glyceryl ether phosphatides of brain, heart, marrow, muscle, and spleen represent 4.5–12.0% of their total phospholipids. Higher concentrations of glyceryl alkyl than of alk‐l‐enyl ethers were found in the neutral lipids whereas the glyceryl alk‐l‐enyl ethers were found to predominate in the phospholipids.
The effect of a polyunsaturated diet upon adipose‐tissue fatty acids in young coronary males. A five‐year cohort study
Authors: Fleischman Alan I. , Hayton Thomas , Bierenbaum Marvin L. , Watson Portia
Published: November 2006

The fatty acid composition in the adipose tissue of 38 electrocardiographycally confirmed coronary males, mean age 43.7 years, at ideal weight on a 30%‐of‐calories controlled‐fat diet, containing approximately 11.4% of calories as linoleic acid, was studied. The initial linoleic acid concentration in the adipose tissue was approximately 11 mole % of total fatty acids; for approximately the first 12 months it rose slightly and then rapidly increased to about 20% after 24 months. The overall response is sigmoidal in form and fits the equation: 1/y=0.025+0.066 (0.975)x in which y represents the adipose tissue linoleate as mole percentage of total adipose tissue fatty acids and x is the time in months.

The relative increase in linoleic acid is not attributable to a decrease in any specific fatty acid.
Metabolism of lipids in rat testes: Interconversions and incorporation of linoleic acid into lipid classes
Authors: Nakamura Masami , Privett O. S.
Published: November 2006

Studies are reported on the mode of incorporation of linoleic acid into lipid classes of testicular lipids. 1‐14C‐linoleic acid was injected into the testes of adult rats of the Sprague‐Dawley strain. Groups of animals were killed at 1, 3, 6, 12, 24 and 48 hr after injections of the radioactive linoleic acid. The testes of each animal and livers of some animals were excised. Fatty acid and lipid class comkposition of the extracted lipids of the testes of each animal were determined as well as the distribution of radioactvity in these compounds. Radioactive linoleic acid and fatty acids derived from it by interconversion and catabolism were incorporated into all the lipid classes. Incorporation of linoleic acid into the lipid classes was much faster than its interconversion or catabolism to other fatty acids. The importance of the fatty acid pool in the mode of incorporation of the fatty acids into the lipid classes is demonstrated.
Analysis of mixtures of stigmasterol, stigmastanol and sitosterol
Authors: Rosenstein Fumiko U. , Kircher Henry W.
Published: November 2006

Hydrogenation of stigmasterol yields mixtures of the three title sterols. Stigmasterol was clearly separated from the other two by gas liquid chromatography; a standard curve was constructed relating the height of its peak to its concentration in the mixture. The total unsaturation was measured by a dibromopyridine sulfate‐thiosulfate procedure. The unsaturation contributed by previously determined stigmasterol was subtracted from the total to leave that contributed by sitosterol, whose concentration in the mixture was then calculated. The amount of stigmastanol, whose presence was qualitatively determined by thin layer chromatography after bromination of the mixture on the plate, was obtained by difference. When suitable corrections were made, based on analysis of known mixtures, the concentrations of three sterols in hydrogenation mixtures could be calculated.
Autoxidation of polyunsaturated fatty esters on Silica
Authors: Slawson Vida , Adamson Arthur W. , Mead James F.
Published: November 2006

The stability of unsaturated methyl esters of fatty acid adsorbed on silica gel and silicic acid was studied by gas liquid chromatographic estimation of disappearance relative to a saturated internal standard. Variables included silica‐ester ratio, agitation, adsorbent particle size, and degree of unsaturation. Under the conditions of the experiment, destruction of substrate unsaturated ester at 80 C was more a function of time than of unsaturation or initial purity.
Cholestanol and plant sterols in pigeon skin
Authors: Ravi Subbiah M. T.
Published: November 2006

Cholestanol (4.6%) and plant sterols (0.2%) have been demonstrated, for the first time, in avian skin by argentation and gas liquid chromatography. In contrast to results of previous studies with rat and human skin, cholestanol represented a significant amount in the pigeon. The proportion of campesterol was always higher than that of β‐sitosterol.
Tumor lipids: Comparison of glyceryl ethers of mouse and insect tumors
Authors: Welch Mary F.
Published: November 2006

Examination of the lipids of two tumor‐bearing mutant strains of fruit fly reveal that they do not have the elevated content of glyceryl ethers typical of many neoplasms of higher animals. Glyceryl ether diesters were absent, and the amounts of alkyl and alk‐1‐enyl glyceryl ethers of tumorous and normal tissues were similar.
Polyprenols of beef and human pituitary glands
Authors: Carroll K. K. , Vilim A. , Woods M. C.
Published: November 2006

An unknown lipid previously isolated in our laboratory from beef and human pituitaries was shown to have the same structure as dolichol from pig liver. Beef pituitaries contained ca. 130 mg/kg wet tissue, of which ca. 25% was esterified to fatty acids. Human pituitaries contained ca. 1.4 g/kg, mainly as the free alcohol.
Dimorphotheca sinuata lipoxygenase: Formation of 13‐L‐hydroperoxy‐cis‐9,trans‐11‐octadecadienoic acid from linoleic acid
Authors: Gardner H. W. , Christianson D. D. , Kleiman R.
Published: November 2006

Lipoxygenase (EC 1.13.1.13) from the seed ofDimorphotheca sinuata oxidized linoleic acid to predominantly 13‐L‐hydroperoxy‐cis‐9,trans‐11‐octadecadienoic acid. When the reaction proceeded at pH 6.9, the 13‐hydroperoxide was the only isomer detected; but at pH 5.1, the 13‐isomer was 92% of the total, the remaining 8% being the 9‐hydroperoxide. At both pH's small amounts of hydroxyoctadecadienoic acid accumulated during the reaction. This acid from the pH 6.9 reaction was analyzed as 13‐hydroxy‐cis,trans‐octadecadienoic. The postulate advanced by many workers that dimorphecolic acid, 9‐D‐hydroxy‐trans‐10,trans‐12‐octadecadienoic acid, is biosynthesized via a lipoxygenase product was not proved. Although the product specificity ofD. sinuata lipoxygenase is like that of lipoxygenase type 1 from soybeans, its inactivity at pH 9 demonstrated that it is a novel enzyme.
Regulation of hepatic cholesterol synthesis from mevalonate in suckling and weaned rats
Authors: Shah S. N.
Published: November 2006

The conversion of mevalonic acid into total nonsaponifiable lipids (NSF) and digitonin precipitable sterols (DPS) by 5000 g liver supernatant fractions was compared in suckling and weaned rats. The incorporation of mevalonate into both NSF and DPS was low in fractions from suckling rats and very high in fractions from weaned rats. The results indicate that the activities of one or more of the enzymes catalyzing the conversion of mevalonate into squalene and squalene into cholesterol change after weaning and may act as regulatory step(s) for cholesterol synthesis in the livers of suckling rats. It is suggested that the reduced synthesis of cholesterol in the liver of suckling rats is caused by the cholesterol in the maternal milk, and the rapid rise in cholesterol synthesis after weaning is due in part to the dietary change accompanying weaning, and in part to an increased need for cholesterol by developing liver.
Changes in structure of triglycerides from maturing kernels of corn
Authors: Weber Evelyn J.
Published: November 2006

Kernels of corn inbred H51 were collected at five intervals after hand pollination. The triglyceride content of the total lipids increased from 8.6% at 10 days after pollination to 78.3% at 60 days. The most active period of triglyceride synthesis occurred from 20 to 45 days after pollination, when the weight of triglycerides per kernel increased from 1.1 to 7.5 mg. Over all the collection periods the percentages of palmitic, linoleic and linolenic acids decreased while oleic acid increased, but from 30 to 60 days after pollination the fatty acid composition of the triglycerides was nearly constant. Stereospecific analysis revealed a general fatty acid pattern for the triglycerides, in which the concentration of the saturated acids was highest in position 1, linoleic acid in 2 and oleic acid in 3. From 20 to 60 days after pollination there was little change in the fatty acid composition at the 1 position, but the largest changes occurred at the 3 position where palmitic and oleic acids decreased 5.1% and 7.3%, respectively, and linoleic acid increased 13.4%. The variations in the molecular species of the triglycerides were determined by silver nitrate thin layer chromatography and were found to be small from 20 to 60 days after pollination, except for an increase in trilinolein from 5.2 to 11.9%. Stereospecific analyses of four major triglycerides species, SMD, M2D, SD2, and MD2, revealed larger changes in fatty acid distribution at individual positions during maturation than were apparent from analyses of the total triglycerides.
Absorption and biliary secretion of intraperitoneally injected 3β‐methoxycholest‐5‐ene‐4‐14C in the rat
Authors: Norcia L. N.
Published: November 2006

Following ip injection of 1 mg amounts of methoxycholestene‐4‐14C into normal intact rats, the amount of label in the whole liver was measured at different time intervals in different animals. These studies indicated that most of the injected compound was absorbed by or before 12 hr. In bile duct‐cannulated rats the secretion of label from ip injected methoxycholestene‐4‐14C or cholesterol‐4‐14C into bile was usually less during the first 24 hr than during the second 24 hr after injection. Studies on the nature of the labeled compounds in the bile following ip injection of methoxycholestene‐4‐14C indicate that most of the label is present in metabolites, 47% of the label in cholic acid and 31% in chenodeoxycholic acid.
Occurrence of (+)‐erythro‐2,3‐dihydroxyhexacosanoic acid in cerebrin from the yeastSaccharomyces cerevisiae
Authors: Proštenik M. , Kljaic K. , Weinert M.
Published: November 2006

(+)‐Erythro‐2,3‐dihydroxyhexacosanoic acid was found in a mixture of cerebrins (ceramides containing sphingosines and phytosphingosines) from the yeastSaccharomyces cerevisiae. The structure was deduced on the basis of elemental analyses, gas liquid chromatography and thin layer chromatography of the appropriate derivatives of the acid and its oxidation products.
α‐Oxidation of 2‐hydroxy tetracosanoate in the rat
Authors: Lippel Kenneth , Mead James F.
Published: November 2006

Four hours after oral administration of uniformly tritiated 2‐hydroxy tetracosanoate, most of the dose was recovered in the lipids of the digestive organs and liver of the rat. In contrast to the unchanged substrate detected in the lipids of the stomach tissue, the radioactivity recovered from the cells of the intestine and from the liver was predominatly in saturated fatty acid moieties of complex lipids and the small per cent of recovered hydroxy tetracosanoate was also incorporated into these lipids.